Abstract:
Various computing devices, thermal solutions and enclosures are disclosed. In one aspect, a computing device enclosure is provided that includes a first compartment that has a first upper side and is adapted to house the computing device and a liquid cooling device. The computing device has at least one heat generating component operable to transfer heat to the liquid cooling device. A second compartment has a lower side that includes an air inlet and a second upper side that has an air outlet. The second compartment is adapted to house a head exchanger to remove hear transferred to the liquid cooling device. A hub connects the first second compartment to the first compartment in spaced apart relation so as to leave a gap between the first upper side and the lower side.

Description:
BACKGROUND OF THE DISCLOSURE 
       [0001]    This invention relates generally to electronic devices, and more particularly to computing device enclosures and thermal management systems for computing devices. 
         [0002]    Many types of conventional computers consist of a one or more circuit boards housed with an enclosure or case. ATX and microATX represent some conventional standard case sizes. A few conventional case designs incorporate two side-by side compartments or sometimes vertically stacked compartments. In many conventional designs, thermal management is provided by a heat sink or spreader and a cooling fan. However, some conventional computers generate more heat than can be adequately managed by air flow alone. These designs often resort to a liquid cooling system. 
         [0003]    Several technical issues are presented by conventional liquid cooling and case designs. Many conventional liquid cooling systems employ multiple radiators. The placement of these multiple radiators is normally driven by whatever the prevailing standard enclosure form factors are, such as ATX/microATX, etc. These standard form factors do not allow the most efficient use of space. In addition, typical conventional liquid cooling systems using standard components tend to be relatively large and do not allow for much customization or implementation of unique form factors. Some conventional dual compartment computer cases tend to draw air passed first through, and thus preheated by, one compartment and into the second compartment that houses the liquid cooling radiators. This preheating reduces the efficacy of the radiator. 
         [0004]    Many current liquid cooling computer systems encompass multiple cold plates which are mounted to various high power devices within the system. This leads to higher system complexity and size since these various cold plates must be routed together via a tubing network within the system. Typically, the cold plates must be interconnected and routed into a radiator for the heat to be removed from the system. Since each cold plate has one inlet and one outlet for the fluid, this requires more hardware and interconnection between each cold plate (tubing, fitting, etc.). These networks of cold plates are not optimized to fit within a system enclosure and therefore leads to wasted space and greater assembly complexity within the system enclosure. 
         [0005]    The present invention is directed to overcoming or reducing the effects of one or more of the foregoing disadvantages, among others. 
       SUMMARY OF THE :INVENTION 
       [0006]    In accordance with one aspect of the present invention, a computing device enclosure is provided that includes a first compartment that has a first upper side and is adapted to house the computing device and a liquid cooling device. The computing device has at least one heat generating component operable to transfer heat to the liquid cooling device. A second compartment has a lower side that includes an air inlet and a second upper side that has an air outlet. The second compartment is adapted to house a heat exchanger to remove heat transferred to the liquid cooling device. A hub connects the second compartment to the first compartment in a spaced apart relation so as to leave a gap between the first upper side of the compartment and the lower side of the second compartment. 
         [0007]    In accordance with one aspect of the present invention, a computing device enclosure is provided that includes a compartment with a first portion that is adapted to house the computing device and a liquid cooling device. The computing device may have at least one heat generating component operable to transfer heat to the liquid cooling device. The second portion of the compartment is adapted to house a heat exchanger to remove heat transferred to the liquid cooling device. The compartment may include air inlets and air outlets for venting around its perimeter. For example, the compartment may include air inlets and air outlets around its middle portion to allow for venting. 
         [0008]    In accordance with another aspect of the present invention, a computing device is provided that includes a first compartment that has a first upper side and a first heat generating component positioned in the first compartment. A liquid cooling device is positioned in the first compartment and in thermal contact with the first heat generating component. In one example, the heat generating component may be a power supply, or a component of a power supply, such as a voltage regulator. A second compartment has a lower side that includes an air inlet and a second upper side including an air outlet. A hub connects the second compartment to the first compartment in spaced apart relation so as to leave a gap between the first upper side and the lower side. A heat exchanger is positioned in the second compartment and delivers cooling liquid to the liquid cooling device and is operable to exchange heat with air moving from the air inlet through the second compartment to the air outlet. 
         [0009]    In accordance with another aspect of the present invention, a liquid cooling device for a computing device is provided that includes an internal chamber to permit cooling liquid to pass there through. The liquid cooling device may be in thermal contact with a first heat generating component of the computing device and a second heat generating component of the computing device. For example, the liquid cooling device may be in thermal contact with a component of a power supply. In one example, the liquid cooling device may include a first side adapted to thermally contact a first heating generating component of the computing device, and a second side adapted to thermally contact a second heat generating component of the computing device. 
         [0010]    In accordance with another aspect of the present invention, a computing device is provided that includes a first compartment that has a first upper side. A first circuit board is positioned in the first compartment and has a first heat generating component. A second circuit board is positioned in the first compartment in vertical spaced apart relation to the first circuit board and has a second heat generating component. A liquid cooling plate is positioned in the first compartment and includes a first portion in thermal contact with the first heat generating component and a second portion in thermal contact with the second heat generating component. In one example, the liquid cooling plate has a first side in thermal contact with the first heat generating component and a second side in thermal contact with the second heat generating component. A second compartment has a lower side that includes an air inlet and a second upper side that includes an air outlet. A hub connects the second compartment to the first compartment in spaced apart relation so as to leave a gap between the first upper side and the lower side. 
         [0011]    In accordance with another aspect of the present invention, a method of manufacturing a computing device enclosure is provided that includes fabricating a first compartment having a first upper side and being adapted to house the computing device and a liquid cooling device. The computing device has at least one heat generating component operable to transfer heat to the liquid cooling device. A second compartment is fabricated that has a lower side that includes an air inlet and a second upper side that includes an air outlet. The second compartment is adapted to house a heat exchanger to remove heat transferred to the liquid. cooling device. The second compartment is connected to the first compartment in spaced apart relation so as to leave a gap between the first upper side and the lower side. 
         [0012]    In accordance with another aspect of the present invention, a method of thermally managing a computing device that has a first heat generating component is provided. The method includes placing the first heat generating component in a first compartment of an enclosure. The first compartment has a first upper side. The enclosure includes a second compartment with a second upper side and a lower side and is connected in spaced apart relation to the first compartment by a hub so as to leave a gap between the first upper side and the lower side. A liquid cooling device is placed in the first compartment and is in thermal contact with the first heat generating component. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The foregoing and other advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which: 
           [0014]      FIG. 1  is a pictorial view of an exemplary computing device that includes a multi-compartment enclosure; 
           [0015]      FIG. 2  is an overhead view of the exemplary computing device shown in  FIG. 1 ; 
           [0016]      FIG. 3  is a sectional view of  FIG. 2  taken at section  3 - 3 ; 
           [0017]      FIG. 4  is a sectional view like  FIG. 3 , but of an alternate exemplary computing device that includes a multi-compartment enclosure; 
           [0018]      FIG. 5  is a sectional view of  FIG. 4  taken at section  5 - 5 ; 
           [0019]      FIG. 6  is a sectional view of  FIG. 4  taken at section  6 - 6 ; 
           [0020]      FIG. 7  is a sectional view like  FIG. 3 , but of another alternate exemplary computing device that includes a multi-compartment enclosure; 
           [0021]      FIG. 8  is a sectional view of  FIG. 7  taken at section  8 - 8 ; 
           [0022]      FIG. 9  is a sectional view of  FIG. 7  taken at section  9 - 9 ; and 
           [0023]      FIG. 10  is a pictorial view of another exemplary computing device that includes a multi-compartment enclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    Various embodiments of a computing device and enclosure are disclosed. In one arrangement, the computing device is positioned in a lower compartment of a multi-compartment enclosure along with a liquid cooling device, such as a cooling plate(s). The cooling plate may be in thermal contact with one more heat generating components of the computing device. A heat exchanger and liquid pump may be positioned in a second, upper compartment of the enclosure. The first and second compartments are connected in vertical spaced apart elation by a hub so as to leave a gap between the lower and upper compartments. The hub includes an internal bore to accommodate liquid flow lines. The arrangement flows air through the upper compartment past a heat exchanger, but with little if any pre-heating from the lower compartment. Additional details will now be described. 
         [0025]    In the drawings described below, reference numerals are generally repeated where identical elements appear in more than one figure. Turning now to the drawings, and in particular to  FIGS. 1 and 2 , therein are shown a pictorial view and an overhead view of an exemplary embodiment of a computing device  10  that includes a housing  15  that encloses various electronics and cooling devices (not shown) that will be described in more detail below and shown in subsequent figures. The housing  15  may be subdivided into a lower compartment  20  and an upper compartment  25  connected together, but vertically displaced to establish a gap  27 . The lower compartment  20  and the upper compartment  25  may be connected by way of a hub  30 . As described in more detail below, the lower compartment  20  may enclose a variety of different types of electronic components. Accordingly, the lower compartment  20  may be populated with plural input/output ports collectively labeled  35 . The ports  35  may be video ports, data ports, audio ports, combinations of these or other types of ports as desired. In this illustrative embodiment, the upper side  37  of the upper compartment  25  may be configured with an air outlet  40  in the form of the grid or mesh-like design depicted that permits the discharge of cooling air  45 . The air outlet  40  may have a rectangular mesh as shown, a diamond-shaped mesh or many other types of shapes and configurations. As shown in subsequent figures, a lower side  50  of the upper compartment  25  may similarly include a structure such as a grid or mesh to provide intake air. An upper side  55  of the lower compartment  20  may be a top wall that does not include capability for air flow. However, as described in alternate embodiments below, the upper side  55  may also incorporate air flow passages. 
         [0026]    The gap  27  and the closed upper side  55  permit air  45  to be drawn into the gap  27 , passed through the upper compartment  25  and discharged from the outlet  40  without first undergoing a preheating process, as is common in many conventional multi-compartment case designs. As better seen in  FIG. 2 , both the upper and lower compartments  20  and  25  may have a generally rectangular footprint. However, these footprints may be square, or other shapes as desired. Similarly, while in this illustrative embodiment the sidewalls  60  of the lower compartment  20  and the sidewalls  65  of the upper compartment  25  may be substantially vertical, in alternate embodiments the sidewalls  60  and  65  may be inwardly sloped, outwardly sloped or some other configuration as desired. 
         [0027]    A variety of materials may be used to fabricate the lower compartment  20 , the upper compartment  25  and the hub  30 . Exemplary materials include, for example, aluminum, plastics, stainless steel, copper, combinations of these or others. The components of the upper and lower compartments  20  and  25  may be manufactured using casting, stamping, forging, molding, machining or other well-known fabrication techniques. 
         [0028]    Attention is now turned also to  FIG. 3 , which is a sectional view of  FIG. 2  taken at section  3 - 3 . As shown in  FIG. 3 , the lower compartment  20  may include an interior chamber  70  that may house a variety of components. For example, a circuit board  75  and another circuit board  80  may be positioned in the enclosure  70  and held in position by suitable posts, fasteners or other structures that are not visible. The circuit board  75  may be any variety of different types of electronic boards. The same is true for the circuit board  80 . The circuit board  75  may include a variety of heat generating components, one of which is visible and labeled  85  and the circuit  25  board  80  may similarly include a variety of heat gene components, one of which is shown and labeled  90 . The heat generating components  85  and  90  may be any of a variety of different types of electrical or electronic devices, such as, microprocessors, graphics processors, combined microprocessor/graphics processors sometimes known as application processing units, application specific integrated circuits, memory devices, systems on a chip, optical devices, passive components, interposers, or other devices. In an exemplary embodiment, one or more of the heat generating components  85  and  90  may be processors, such as an accelerated processing unit (APU), a central processing unit (CPU), a digital signal processor (DSP), or any other processor. The disclosed circuit boards, such as circuit board  75  and the circuit board  80  may be electrically connected to each other in a variety of ways. In this illustrative embodiment, the circuit boards  75  and  80  may be electrically connected by way of the disclosed flex connector  95  and respective flex terminals  100  and  105  on the circuit boards  75  and  80 , respectively. Optionally, a myriad of other types of electrical connection schemes may be used to interconnect the circuit boards  75  and  80 . 
         [0029]    Thermal management for the heat generating components  85  and  90  may be provided by a liquid cooling device  110 . The term “liquid” used herein is not intended to exclude the possibility of two phase flow. The liquid cooling device  110  may take on a variety of configurations. In an exemplary embodiment, the liquid cooling device  110  may be a cooling plate with an internal chamber  112  to permit flow of a cooling liquid  113 , such as water, glycol or any other suitable coolant, such as a gas coolant. This internal chamber  112  is unitary in this embodiment, but may be shared among multiple chambers as discussed with other embodiments. The liquid cooling device  110  is advantageously designed to provide a shared liquid cooling capability for the heat generating components  85  and  90 . In this illustrative embodiment, the heat generating component  85  is in thermal contact with a lower side  115  of the liquid cooling device  110  and the heat generating component  90  is positioned in opposition to the heat generating component  85  and thus in thermal contact with an upper side  120  of the liquid cooling device  110 . This thermal contact may be facilitated by way of thermal greases or other thermal interface materials as desired. The liquid cooling device  110  is connected to a fluid supply line  125  and a fluid discharge line  130 . The fluid supply line  125  is operable to deliver cooling liquid from a pump  135  that is positioned in an interior chamber  140  of the upper compartment  25 . The fluid discharge line  130  is connected and operable to deliver cooling liquid from the liquid cooling device  110  to a heat exchanger  142  in the upper compartment  25 . The fluid supply line  125  and the fluid discharge line  130  are routed through the hub  30  and more specifically through the open internal bore  145  of the hub  30 . 
         [0030]    The liquid cooling device  110  may be provided with a variety of different types of internal structures to facilitate the transfer of heat from the cooling liquid, one schematically depicted and labeled  150 . For example, a single baffle wall  155  is illustrated, however as just noted, there can be multiple types of the internal structures to increase the surface area contact with the cooling liquid  150 . The liquid cooling device  110  and any disclosed alternatives may be constructed of well-known materials, such as aluminum, copper, stainless steel, combinations or other materials, and using well-known techniques, such as casting, machining, punching, forging, soldering, welding, combinations of these or others. 
         [0031]    Access to the chamber  70  of the lower compartment  20  may be provided in a variety of ways. In the illustrated embodiment, a removable lower panel  160  may be connected to the lower compartment  20  by way of multiple fasteners for screws  165 . A variety of other techniques may be used to secure the hatch or panel  160  to the lower compartment  20 . The lower hatch  160  may be provided with plural foot pads  170  to provide a cushioned support for the computing device  10  when seated on a surface (not shown). The pads  170  may number three of more. 
         [0032]    The hub  30  may consist of mating halves  175  and  180  that may be joined at a threaded joint  185  or other type of joint as desired. The position of the joint  185  and thus the vertical extent of either or both of the mating halves  175  and  180  may be varied as desired. Here, the mating halves  175  and  180  may be integrally formed with the lower compartment  20  and the upper compartment  25 , respectively. However, this need not be the case and thus the components of the hub  30  may be separately fabricated and thereafter attached to the lower compartment  20  and the upper compartment  25 , respectively. While hub  30  is depicted as being round, other shapes could be used. 
         [0033]    The structure and function of the upper compartment  25  will now be described in conjunction with  FIG. 3 . Additional components of the liquid cooling system may be housed in the internal chamber  140  and include, for example, the aforementioned liquid pump  135  as well as the heat exchanger  142  and a cooling fan  190 . The heat exchanger  142  may be configured as a radiator or otherwise. The liquid pump  135 , the liquid cooling device  110  and the heat exchanger  142  form a fluid circuit. In this regard, liquid pump  135  is connected to, and receives cooled liquid from, the heat exchanger  142  by way of a supply line  195 . The liquid pump  135  delivers the cooling liquid to the liquid cooling device  110  and away therefrom and to the heat exchanger  142  by way of the supply line  125  and the discharge line  130 , respectively. The supply line  125  may connect to the liquid pump  135  by way of a coupling  197 , which may be a threaded coupling, soldered coupling or other types of fastening techniques and couplings. The discharge line  130  may be similarly connected to the heat exchanger  142  by a coupling  198 . The same types of connections (schematically shown) may be used for other portions of the supply line  125  and discharge line  130  and the supply line  195 . The heat exchanger  142  is schematically depicted but may consist of well-known structures used in radiator designs such as plural fins interspersed with multiple flow and discharge lines. 
         [0034]    As noted briefly above, the underside  50  of the upper compartment  25  may be provided with an air inlet  205  in the form of the disclosed mesh structure, which may be substantially like the mesh structure or alternatives thereto of the upper compartment  25  described above and shown in  FIGS. 1 and 2 . In this way, when the fan  190  is operating, cooling air  45  may be drawn into the gap  27 , up through the air inlet  205 , past surfaces of the heat exchanger  142  and discharged out of the air outlet  40  at the upper side  37  of the upper compartment  25 . The air  45  is not moved through the lower compartment  20  where it would be heated prior to movement into and through the upper compartment  25 . The fan  190  may have a hub portion  217  and a blade portion  218 . The heat exchanger  142  and the fan  190  are positioned in the upper compartment  25  such that the hub portion  217  is somewhat in vertical alignment with the hub  30 . With this arrangement, very little preheated air is drawn up through the inlet  205  prior to contacting the heat exchanger  142 . This is in contrast to many conventional dual compartment computer cases  7 h e cooling air delivered to a water cooling system is delivered from the confines of an enclosure that includes heat generating components which tends to preheat that intake air that passes over the liquid cooling system. 
         [0035]    In the foregoing illustrative embodiment depicted in  FIG. 3 , the liquid cooling device  110  is sandwiched between the heat generating components  85  and  90  and thus uses opposite sides  115  and  120  to establish thermal contact with those components. However, other arrangements are envisioned. In this regard, attention is now turned to  FIG. 4 , which is a sectional view like  FIG. 3  but of an alternate exemplary embodiment of a computing device  10 ′. The computing device  10 ′ may share many attributes with the computing device  10  described above. Thus, the computing device  10 ′ may include the aforementioned lower compartment  20  and upper compartment  25  as well as the hub  30 . Like the other illustrative embodiments, the upper compartment  25  may include the heat exchanger  142 , the cooling fan  190 , and the liquid pump  135 , all of which are used to provide thermal management by drawing cooling air  45  through the air inlet  205  and discharged out the air outlet  40 . Similarly, the liquid pump  135  is connected to a supply line  125  and a discharge line  130 . However, a liquid cooling device  110 ′ utilized to provide thermal management for heat generating components within the lower compartment  20  has a different configuration than the above described embodiment. In this illustrative embodiment, a heat generating component  85  may be connected to a circuit board  220  and a heat generating component  90  may be connected to a circuit board  225 . The heat generating components  85  and  90  may be configured as described above in conjunction with the components  85  and  90 . The circuit board  220  may be connected electrically to the circuit board  225  by way of a riser connector  230  which may be configured like any of a variety of well-known riser connectors. In this illustrative embodiment, and because the riser connector  230  is utilized, the heat generating component  85  faces upward and is at a lower elevation then the heat generating component  90  which is facing downward. To provide thermal management for these heat generating components  85 ′ and  90 ′ that are spatially oriented as shown, the liquid cooling device  110 ′ may include an upper cooling plate  235  and a lower cooling plate  240  that is in fluid communication with the upper cooling plate  235 . The upper cooling plate  235  includes a body  242  and a lid  243  that may be detachably connected to the body  242 . The body  242  and the lid  243  enclose an internal chamber  244 . The usage of a lid  243  facilitates the formation, by casting, machining or otherwise, of various internal passages and reservoirs to be described below. The lid  243  may be secured to the body  242  by soldering, adhesives, screws, welds or other fastening techniques. The body  242  may include a block  245 , which projects downwardly to establish thermal contact with the heat generated component  85 ′. The block  245  includes a chilled liquid inlet reservoir  250 . The lower cooling plate  240  similarly may include a body  252  and a lid  253  that enclose an internal chamber  254  and function and may be constructed like the body  242  and lid  243 . The internal chambers  244  and  254  function as a shared internal chamber since they are in fluid communication. 
         [0036]    Additional details of the upper cooling plate  235  may be understood by referring to  FIG. 5  which is a sectional view of  FIG. 4  taken at section  5 - 5 . Note that because of the location of section  5 - 5 , the lid  243  is shown in section while the underlying body  242  is not. The chilled liquid inlet reservoir  250  is in fluid communication with the fluid supply line  125  that is connected to the liquid pump  135 . Chilled liquid delivered to the reservoir  250  then passes into a longitudinal channel  255  that terminates at a Y-branch  260 . Liquid flow is represented by the arrows  262 . One branch  265  of the Y-branch  260  terminates in a fluid passage  270  and the other branch  275  terminates in another fluid passage  280 . The fluid passage  270  is shown and labeled also in  FIG. 4  but it should be understood that the fluid passage  270  is shown out of rotation in  FIG. 4  so that it can be seen in the sectional view that is  FIG. 4 . The fluid passages  270  and  280  deliver chilled liquid down through suitable openings in the circuit board  225  that are not separately labeled. The chilled liquid passes through the body of the cooling plate  240  and loops back up in a J-shape or otherwise fashion to the internal chamber  254  of the lower cooling plate  240 . After passing through and contacting various features inside the internal chamber  254 , the liquid passes out of the chamber  254  down into a fluid passage that may be configured like the fluid passages  270  and  280  that feed up through the cooling plate  240  through suitable openings in the circuit board  225  and ultimately terminating in a U-shaped channel  290  in the lid  243  of the upper cooling plate  235  as best seen in  FIG. 5 . Again it should be noted that the fluid pipe or passage  290  shown in  FIG. 4  is shown out of rotation in  FIG. 4 . Ultimately the U-shaped channel  295  is in fluid communication with the fluid discharge line  130  that leads back to the liquid pump  135 . In this way, the chilled liquid at its lower temperature may be delivered to the upper cooling plate  235  and ultimately to the block  245 , which is shown in dashed lines in  FIG. 5  such that, if the heat generating component  85 ′ dissipates a greater amount of heat than the heat generating component  90 , the lower temperature liquid can be delivered first to the heat generating component  85  and thereafter passed through from the upper cooling plate  235  to the lower cooling plate  240  to deliver still effective cooling liquid but at a subsequently higher temperature to the heat generating component  90 . Note that the block  245  not only provides the capability to deal with elevation differences between heat generating components  85  and  90  but also provides a greater physical mass in order to transfer heat away from the heat generating component  85  and to facilitate heat transfer with a cooling fluid. The upper and lower cooling plates  235  and  240  may be constructed of a variety of materials, such as copper, aluminum, stainless steel, combinations of these or other materials. 
         [0037]    Additional details of the lower cooling plate  240  may be understood by referring now also to  FIG. 6 , which is a sectional view of  FIG. 4  taken at section  6 - 6 . Note that because of the location of section  6 - 6 , the body  252  is shown in section and the lid  253  is not visible. Here, the body  252  of the lower cooling plate  240  is shown in section to reveal also the internal chamber  285 . The fluid passages or tubes  270  and  290  that appear as J-shaped tubes in  FIG. 4  appear as circles and phantom lines in  FIG. 6 , as do the J-shaped tubes  280  and  300 , due to the location of section  6 - 6 . Note that the internal chamber  285  may be provided with plural baffles or other textured surfaces  305  to simply provide a greater surface area for heat transfer with the cooling fluid. The number arrangement of such baffles  305  may be subject to great variety. 
         [0038]    Another alternate embodiment of a computing device  10 ″ may be understood by referring now to  FIG. 7 , which is a sectional view like  FIG. 3 . The computing device  10 ″ may share many attributes with the other disclosed embodiments, such as the lower compartment  20 , the upper compartment  25 , the hub  30 , the heat exchanger  142  and the cooling fan  190  both positioned in the internal chamber  140  of the upper compartment  25 . However, the lower compartment  20  may house a different configuration of electronic components that may benefit from an alternative configuration of heat exchangers. In this illustrative embodiment, a heat generating component  85 ″ may be connected to a circuit board  310  and a heat generating component  90 ″ may be connected to a circuit board  315 . In this illustrative embodiment, the heat generating component  90 ″ faces downward and so does the heat generating component  85 ″. The circuit board  310  may be electrically connected to the circuit board  315  by way of a riser connection  320  which may be configured like the riser connection  230  described above. To provide thermal management for the heat generating components  850  and  900 , a liquid cooling device  110 ″ may include a lower cooling plate  325  and an upper cooling plate  330 . The upper cooling plate  330  is in fluid communication with the lower cooling plate  325  by way of one or more fluid passages, one of which is visible in  FIG. 7  and labeled  335 . Note that the passage  335  is shown out of rotation in  FIG. 7  and will be more evident during the description of  FIG. 9  to follow. The lower cooling plate  325  may include a body  337  and lid  338  connected to the body  337  that together enclose an internal chamber  339 . The upper cooling plate  330  may similarly include a body  340  and a lid  341  connected to the body  340  that together enclose an internal chamber  342 . The bodies  337  and  340  and the lids  338  and  341  may function and be constructed like the other body and lid alternatives disclosed herein. Thus, the internal chambers  339  and  342  function as a shared internal chamber since they are in fluid communication. In this illustrative embodiment, the liquid pump  135  may be positioned in the internal chamber  70  of the lower compartment  20 . 
         [0039]    Additional details of the lower cooling plate  325  may be understood by referring now also to  FIG. 8 , which is a sectional view of  FIG. 7  taken at section  8 - 8 . Because of the location of section  8 - 8 , the body  337  of the lower cooling plate  325  and the liquid pump  135  are shown in section but the lid  338  is not visible. Note that the body  337  of the lower cooling plate  325  may include a cutout  343  to accommodate the placement of the pump  135 . As shown in  FIG. 7 , the pump  135  may include a chilled liquid intake line  345  which is connected to the heat exchanger  142  and receives chilled liquid therefrom. In addition, the pump includes a chilled liquid delivery line  350  that is connected to the lower cooling plate  325 . That connection between the chilled liquid supply line  350  and the lower cooling plate  325  may occur at a channel  355  in the lower cooling plate  325  that is shown in  FIG. 8 . Fluid may flow through the channel  355  around a plurality of baffles  360 , as indicated by the arrows  365 , and ultimately flow across the width of the cooling plate  325  and into a return channel  370 . The location A of the channel  355  may be a position where liquid from the upper cooling plate  330  is returned to the lower cooling plate  325  as described below in conjunction with  FIG. 9 . The return channel  370  is in fluid communication with a heated water delivery line  385  shown in  FIG. 7  that is connected to the heat exchanger  142 . Simultaneously, cooling liquid flows from the channel  355  up through the conduit  335  and into the upper cooling plate  330 . 
         [0040]    Additional details of the upper cooling plate  330  may be better understood by referring now also to  FIG. 9 , which is a sectional view of  FIG. 7  taken at  9 - 9 . Because of the location of section  9 - 9 , the body  340  is shown in section but the underlying lid  341  is partially visible and not in section. As just noted, a cooling fluid travels from the lower cooling plate  325  up through the conduit  335  and into the upper cooling plate  330  and follows a path indicated by the arrows  390  around a set of baffles  395  and ultimately discharges through a conduit  400 , which may be like the conduit  335  that feeds down into the channel  355  at or around the location A of the lower cooling plate  325  shown in  FIG. 8  where it ultimately may be transferred back to the heat exchanger  142 . Of course the number and configuration of the baffles  395  may be subject to great variety. 
         [0041]    In the foregoing illustrative embodiments of the computing devices  10 ,  10 ′ and  10 ″, the lower compartment  20  generally does not include any type of air inlets or air discharge openings while the upper compartment  25  does. However, and as shown in  FIG. 10 , an alternate exemplary computing device  10  may include a lower compartment  20 , an upper compartment gap  27  and a hub  30  as generally described above. However, the lower compartment  20  may include an air inlet/discharge structure  405  such as the depicted mesh or alternatives disclosed elsewhere herein, and the upper compartment  25  may include the aforementioned air outlet  40  as described above. A portion of the lower compartment  20  is cut away to show that an underside  410  of the lower compartment  20  may also include an air inlet  415  in the form of the depicted mesh or alternatives disclosed elsewhere herein. 
         [0042]    While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.