Cooling ATi Radeon AGP video card (front and back) - Page 1
Forum section: electronics / beginners

author: 13hm13
author_rank: Frequent Contributor
timestamp: September 09, 2020, 04:31:53 pm
content: I have an old (2010) ATi video card -- ASUS ATi (AMD) Radeon HD 3450 512mb AGP DVI/VGA/HDMI Graphics Card -- that still working (always on!!) .GPU temps (per my PC utility SpeedFan, report 35-41C avg. )Twice a year, the fan motor needs oiling, and the fans and heat-sink needs blowing out.On my motherboard, the fan side faces down and this side is face up:Notice the white square pad with the smaller white rectangle protruding out the cut out. I think this is the bottom of the same (??) main GPU that is on the fan side.I put my finger on the small white rectangle and it feels very warm. Using an IR thermometer, I measured ~60C on the white rectangle.So what exactly is the white rectangle, what's that soft white square pad around it, and why isn't it heat-sinked?

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 09, 2020, 11:52:07 pm
content: It does look like a heatsink support/adhesive pad, but I don't think one was installed at the factory ever for that card. At least it shows up on all images of the card I can find on the web, too.You could add a heatsink there, but having it make a good enough (thermal) contact with the chip surface is difficult: there are no holes nearby to use. (The most commonly used method is having plastic studs with springs exerting a relatively constant force, pushing the heatsink to the chip.) That could be the reason Asus didn't have a heatsink there in the first place: they could have hoped to use a heatsink with adhesive pad, but it wouldn't hold too well in beta testing, so they dropped the heatsink and just left the support/adhesive pad.I do believe Asus had passive heatsink versions of the same card, so if you have access to a CNC mill, you could mill a two-sided passive heatsink (using the three holes in the card, replacing the existing fan and fan shroud) to sandwich the GPU and its memory chips, increasing the heat dissipation area a lot. I do not know if there was an aftermarket passive heatsink replacement made by some other company; they do exist for some models, but not all.

author: 13hm13
author_rank: Frequent Contributor
timestamp: September 10, 2020, 01:36:06 am
content: I bought mine brand new from a reputable dealer (Tiger Direct, $66.00 usd) 10 years ago. It came just like that, and all pictures (ebay, etc) show just that white pad w/cutout on the opposite side.Two plastic clips hold that huge top fan/sink assembly "clamped" to the silicon GPU (the GPU does not have metal lid).Not sure what that white rectangle inside square pad is -- a supporting "co-processor" chip? Or might it be a thruhole "flat" heatsink or securing/anchoring device from the main GPU on the fan side?I did affix a small sink with some thermal tape, and I managed to lower GPU sensor temp by 3C and -pointing IR laser-- by about 7C at the tape/heatsink interface.

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 10, 2020, 11:12:20 am
content: Quote from: 13hm13 on September 10, 2020, 01:36:06 amYes, exactly.Quote from: 13hm13 on September 10, 2020, 01:36:06 amMe neither. It could be anything, really. Some chips (Trinamic stepper drivers, for example) are better cooled from the underside, too.Quote from: 13hm13 on September 10, 2020, 01:36:06 amMakes sense, then, why Asus didn't include a heatsink there by default: the thermal connection isn't good enough to make sufficient difference in real life use: 60°C isn'tthathot for most ICs. Certainly not hot enough that a 3°C or even 7°C difference would be worth the extra space the heatsink would take, possibly blocking the next expansion slot.But, it does mean that a sandwich-style dual-sided heatsink assembly is quite possible for this card. The main machining on a heatsink "plate" would be to ensure the SMD passives don't touch the heatsink, only that small white square and possibly the RAM chips near the end of the card on this side. (I haven't seen what kind of surface the heatsink inside the fan shroud, under the fan, on the other side has, but I'd quess it too is relatively flat, with some cutouts or recesses milled for passives.)If one had a small mill, or a friend with a metal milling machine, it is something to possibly consider. One can buy two pieces of extruded aluminium heatsink "bar" off fleabay or retail stores for about ten bucks each, so one would only need to drill the three attachment holes (maybe tap them on one side?), and mill a couple of mm (1/16th to 1/8th of an inch) deep recesses outside the hot surfaces for passives to not hit the heatsink. Something very feasible to work out in a local Hacklab, for example.(The reason I am talking about this, is that I have similar needs for a few different Linux single-board computers I have – a couple of Odroids and a La Frite. They're tiny, and fit very nicely into (very affordable) Hammond die-cast aluminium enclosures. I'd like to do new lids for these enclosures, so that the lid itself would act as a heatsink for the entire board. The wiring could be pulled through split grommets in the lid-box seam, making the SBC dust-proof and possibly splash-proof too, perfect for dirty workshop environment mini-computers.)

author: samnmax
author_rank: Regular Contributor
timestamp: September 10, 2020, 11:51:07 am
content: The small chip is an AGP to PCIE bridge. I also had a similar card, and also noticed the chip was very warm. I added a small heatsink using some magnets stuck to the main heatsing screws (layout was different than your card). However, even with the modification, I think the card gave segfaults in Linux so I replaced it.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 10, 2020, 12:09:38 pm
content: Quote from: 13hm13 on September 09, 2020, 04:31:53 pmmine is 10+ years old ATI Radeon HD 4650. comparing mine and your (48W TDP vs 25W TDP) yours should be lower heat generator.https://www.techpowerup.com/gpu-specs/radeon-hd-4650.c233https://www.techpowerup.com/gpu-specs/radeon-hd-3450.c224now i disconnected the fan wire because it grew noisy (even after oiling) and 2 of its fan blades broke off due to careless maintenance cleaning. at first i keep track the temp with Speccy, with fan its 40degC, without it temp stabilizes at 70-80degC, i tried prolonged usage with casing side's cover opened in air conditioned room. i thought if it breaks, i will just replace it with another spare GFX card in store, these old cards are available used and cheap, and i consider it as already broke (fan) anyway. but its still work for many weeks now. the only noise i can hear from my PC now is CPU+PSU fans which is bearable. ymmv.

author: Renate
author_rank: Super Contributor
timestamp: September 10, 2020, 07:08:48 pm
content: Quote from: Mechatrommer on September 10, 2020, 12:09:38 pmAn understandable philosophy.You can lose sleep over the temperature of things or just wait until it dies.I've got a VisionTek ATI 7750x6.It's now in a case on a right angle PCIe x16 adapter which means that the heatsink is facing down.I wouldn't mind a heatsink on the top of the board, but since there are only the 4 screw holes for heat transmission I don't know how useful that would be.

author: 13hm13
author_rank: Frequent Contributor
timestamp: September 10, 2020, 09:16:20 pm
content: Keys to longevity (IME): Keeping devices always on, using clean power ... and, when initially selecting QUALITY components/devices by doing "pre-search" and not buying cheap stuff.BTW: The mbd for that PC is an Asus from Feb 2004, as is the P4 2.8Ghz cpu!I have many much newer PCs, SBCs, phones, laptops around me. All a bit boring ... it's much more fun keeping old guys running ALAP.Having a Status (task) bar temp readout -- and familiarizing yourself with quotidian temps will also help minimize reliability issues. As well as the usual mechanical squeal of fan bearing.

author: cdev
author_rank: Super Contributor
timestamp: September 10, 2020, 09:30:51 pm
content: Why don't you add an additional large diameter, slow fan to your PC's case? A quiet 120 mm fan, you can buy these speed controls to lower the voltage if you want it absolutely quiet. Where you mount it use rubber grommets or rubber fasteners. Its the easiest solution.

author: paulca
author_rank: Super Contributor
timestamp: September 11, 2020, 11:15:28 am
content: 60*C is absolutely fine for a GPU. 60*C is about what mine runs at when flat out with aggressive water cooling. Most GPUs in the past 10 years are absolutely happy anywhere up to 85*C and some 105*C. They will throttle themselves to not over temp and if they do over temp they halt. The only way you are going to kill one would be to completely remove the heatsink and stress test it.

author: Renate
author_rank: Super Contributor
timestamp: September 11, 2020, 11:40:10 am
content: Quote from: cdev on September 10, 2020, 09:30:51 pmFunny, I just built a custom case with a 120 on top.Most motherboards today have lots of PWM fan jacks, no need for anything outboard.If you buy a loose fan (without plug) from an electronic supplier the wire colors could be anything.If you don't have the special plug on hand, a JST XH plug with one alignment rib cut off fits well.

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 11, 2020, 12:03:45 pm
content: I use an ancient 4-channel fan controller (3-pin voltage controlled, no PWM) with four thermocouples, similar to Lamptron FC5V3. It's pure voltage controlled analog design for the fan control, with the digital stuff simply showing the RPM and temperature (with alarm, although I've disconnected that). I've found it best for my own use cases (silent self-made enclosures for desktop machines). For less critical 12V/3-pin fan control use cases, I've used Akasa fan controllers (again, pure analog voltage control designs).

author: LateLesley
author_rank: Frequent Contributor
timestamp: September 11, 2020, 12:23:48 pm
content: Going slightly off topic, you can get kits to cool your GPU, if the original heatsink is dying, and needing frequent maintenance. A new cooler might make this less frequent, and run cooler. Example linked below.https://www.arctic.ac/en/Accelero-L2-Plus/DCACO-V300101-BL

author: 13hm13
author_rank: Frequent Contributor
timestamp: September 11, 2020, 02:49:08 pm
content: Quote from: cdev on September 10, 2020, 09:30:51 pmWhat makes you think there were few or none ALREADY installed? In fact, there are two 120mm fans (front of case behind front filter grille, rear of case). And there is another one inside the PSU that sucks air from inside the mbd area (it's a top mounted ATX psu just above mbd).That said, I could do a bit better job at cable mgmt, improving air flow.The sucky thing about the location of that Radeon card is that the location of that white rectangle hottie is maybe 10mm close to the heatsink of the southbridge (??) chip on the mbd (and that chip also runs at about 50c)

author: 13hm13
author_rank: Frequent Contributor
timestamp: September 11, 2020, 02:56:29 pm
content: Speaking of cooling, one of my Rpi cases came with micro heat-sinks for other (non CPU) chips ....... is this marketing wank, or might there be some genuine benefit here? (e.g., I can see some advantage in terms of improved RF/EMI rejection (via shielding) .... but only if those sinks are grounded).

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 11, 2020, 03:08:20 pm
content: Quote from: 13hm13 on September 11, 2020, 02:56:29 pmI am not an EE, and haven't done any actual measurements with IR cameras or proper temperature measuring equipment, but these tiny heatsinks do seem to help in high-load stability testing on various SBCs (as in, put them on and on high load a previously unstable SBC now runs reliably). Whether it is a matter of heat dissipation to ambient air, or just heat spreading more evenly (both across time and space, the heatsink acting as a "thermal reservoir"), I have no idea.My completely unscientific, out-of-my-ass guess would be, that they actually reduce spot load better than the epoxy resin. In other words, that while the overall heat dissipation is only slightly better (although on some chips very important, if the speed has to be throttled due to die temperatures – I don't know if that is true with various RPi models), the peak temperatures at hot spots are reduced because the aluminium or copper heatsinks spreads the heat more evenly. I do believe e.g. memory chips and similar may benefit from this. Obviously, this would matter more for physically larger dies than for tiny dies.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 11, 2020, 04:16:32 pm
content: Quote from: Nominal Animal on September 11, 2020, 03:08:20 pmthe keyword is surface area. why do you think heatsink is a thin plates with many fins? instead of a solid heavy and thick block of metal? those fins is to increase surface area. why? because the rate of heat dissipation to ambient air is mainly a function of that. another important parm is air flow rate running through the surface area..https://www.engineeringtoolbox.com/convective-heat-transfer-d_430.htmlwe know fan is to increase air flow (forced convection), but without it, convection will still occur naturally (hot gases rise, cooler gases replace their place next to the fins area. perhaps electrically analogy speaking, heatsink will provide low impedance path for the heat to flow to ambient, even withot a fan or air flow (natural convection). treat it like an admitance material (in opposite to resistance material), and more or forced air flow will further increase its admittance. well, i'm not an ME expert either..

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 11, 2020, 04:44:11 pm
content: Quote from: Mechatrommer on September 11, 2020, 04:16:32 pmFor heat dissipation, yes.My point was that even those small heatsinks do have thermal capacitance (thermal mass), and that I suspect that is important here. The typical epoxy polymer casing used in chips does not have much at all thermal mass, so tiny localized heat sources, and pulsing heat sources, can locally heat to temperatures that affect the operation of the chip. Adding a heatsink, even just a small chunk of metal without any fins, would act like a low-pass filter, heat-wise, both spatially and temporally.I do not typically overclock my computers, but I do know that those who overclock memory chips, also use heat spreaders on RAM/DIMMs. These are very much just copper plates with a thermally conductive pad, sandwiching the memory cards on both sides. I do believe they perform the same way: not by increasing surface area, really, but spreading the heat both spatially and temporally, like a low-pass filter.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 11, 2020, 06:54:59 pm
content: Quote from: Nominal Animal on September 11, 2020, 04:44:11 pmit has thermal mass? of course, but is it that important? maybe. if heat dissipation from heatsink surface area is less than the heat generated by IC, then the mass temperature will keep increasing until they find their equilibrium (dT is the factor) if more surface area, dT can be reduced, hence the heatsink and IC's die temperature. thermal mass only usefull during the start of operation, when in equilibrium, thermal mass wont play a role imho, its will just heated up slow and similarly cooled down slow (yes your term capacitance is the correct one). thats why i guess if thermal mass is important, heatsink should have a thick base plate and then fins on top.Quote from: Nominal Animal on September 11, 2020, 04:44:11 pmyes but it will also increase surface area (by small amount because its small), hence dT is reduced as well by some amount.Quote from: Nominal Animal on September 11, 2020, 04:44:11 pmif you look at RAM without heatsink, they are not that very close each other, more like half space is RAM half is empty (pcb area), placing a heat spreader like you said will put a full solid surface area on top, thats is doubling the area already, just on top side, there are also on the bottom side, the empty spaces between spreader and pcb, there air can flow too, and on 4 sides of spreader, it has thickness, means it has side area where they can rub with air.and if you look at this picture, its only small amount of mass added on spreader, if mass is important, they should put a spreader 10x thickness of that, but then when they meet together RAM to RAM in the next slot without providing adequate space for air to flow, you'll see what will happens.. cheer.

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 12, 2020, 02:11:27 pm
content: Quote from: Mechatrommer on September 11, 2020, 06:54:59 pmRight. However, here we do not have a simple case of equilibrium thermodynamics, but something much more complicated.The energy dissipated in the chip is converted to heat. This heat is not generated uniformly in time and space, it depends on the activity. In many cases with computers, especially SBCs, this activity is not steady, but sporadic; pulse-like.Let's do some math. These small (14mm by 14mm by 9mm) aluminium heatsinks typically have about 5g of aluminium. The specific heat capacity of aluminium is about 0.9 J/(g·K), so the heat capacity of such heatsinks is about 4.5 J/K. Since  = [W·s], this means that 4.5 watts in one second (of thermal energy) increases the temperature of the heatsink one Kelvin (or equivalently, by one degree Celsius centigrade). If you think of this as a low-pass filter, and the typical amounts of energy dissipated in these chips, this is very significant.There are two mechanisms the heatsink can dissipate energy to the ambient environment: via thermal radiation, and via thermal conduction. At these temperatures (say, 20°C to 60°C, or roughly equivalently 68°F to 140°F) and thermal energies (on the order of watt or two), the majority is via thermal conduction. (This is why the manufacturer charts, like Enzotech BCC9 copper heatsink charthere(PDF), do not start from zero airflow; without airflow, there is no thermal conduction – the surrounding stand-still air just heats up as the heatsink heats up – and the thermal radiation is usually insignificant. Do note that this does not mean forced air circulation is always necessary; hot air is lighter than cold air, and rises up, and such natural air convection often suffices.)It is obvious that heatsinks can dissipate the extra heat to the ambient environment, and allow the chips to turn more energy into heat – to do more "calculation" or "work". This is not in question here, in my opinion. The question is, can these small heatsinks make a difference on top of memory chips and bus controllers and such, that only get up to say 60°C when used without any heatsinks.As I've mentioned, practical experiments and anecdotal evidence suggests they do on small single-board computers.There are two different situations we should consider separately: 1) when long-term stress tests (say, 15 minutes or longer duration) causes the board to become unreliable (crashing occasionally), and 2) when specific workloads cause the board to become unreliable.The first one is a problem in heat dissipation. You need more airflow (a fan, for example), larger heatsinks (with fins), or both. The heatsink simply cannot dissipate enough energy to the ambient environment, and both the heatsink and the chip get too hot to operate reliably. (This is why e.g. Odroid XU4 with a fan outperforms Odroid XU4Q with a passive heatsink: the CPU must be throttled more often with a passive heatsink, in order not to overheat the CPU.)The second one is the more interesting, more hand-wavy, complex case. For simplicity, let's assume the thermal mass of the plastic/epoxy encapsulating the chip is insignificant, less than 0.1 J/K. The thermal energy generated in the chip is not steady state, but more pulse-train-like. Let's assume the chip encapsulation temperature is a steady 50°C at some point in time (due to work done in the past), when a surge of activity in it generates say five joules of thermal energy. Because of the minuscule heat capacity in the un-heatsinked chip, this will cause a local hot spot where the temperature reaches 100°C. It will rapidly dissipate to the ambient environment, but during the temperature spike, the operation of the chip can be unreliable. Or at least, this is what I think happens.(This definitely depends on the internal structure of the ICs, too. For example, Trinamic stepper drivers should be heatsinked on the bottom, through the PCB. I've never looked at the datasheets of bridge chips or high-capacity dynamic RAM modules, so I don't know if they describe that sort of stuff, but these stepper drivers, and DC-DC converter chips with integrated MOSFETs and/or inductors definitely do.)If we consider both of these cases together, then finned heatsinks in an enclosure with either natural convection airflow or forced airflow via a fan makes a lot of sense, even if small; no question here.The heatsinks are not needed for all chips, only those that can generate the kind of thermal spikes as I mentioned above – the more complex ones, in other words.However, manufacturers prefer not to include heatsinks, if they are not needed in most typical situations. SBCs like Raspberry Pis and Pi clones do not usually run heavy computation/IO loads, the sort of loads where the heatsinks would make a difference. Those who do run maximal loads on their boards, tend to find that adding these small heatsinks does make them run more stably. Adding forced airflow and/or larger heatsinks reduces thermal throttling (because the CPU is typically the main source of heat); but adding that for the CPU only – omitting heatsinks for the bridge/IO/RAM chips – often leads to an unstable machine. All this varies depending on SBC, of course.Compare to a DC-DC converter chip that is rated for 3A without heatsinking, 5A with proper heatsinking; with a load that pulses once a second between 1A and 4A. Do you need a heatsink or not? The average current is only 2.5A. Yet, heatsinking may still be necessary, because this is not steady-state operation.As to memory heat spreaders, there is areasonwhy many are made of copper and not aluminium. I do happen to have a set of Scythe Kama Wing Copper heat spreaders (in a package, never installed), and these are rather massive. (Then again, they have a "wing" that extends in a 45° angle about the width of the DIMM card.) A lot of "overclocked" DIMM sticks already have heat spreaders installed at the factory; and I do not believe it isjustfor heat dissipation (case 1 above), but also for thermal capacitance reasons (case 2 above).(Copper heatsinks are worth the extra cost, in my opinion, only if you have forced airflow but no room for a bigger aluminium heatsink.)I'll happily agree that heat dissipation is the primary reason. I'd even say that the secondary case is quite specific to SBC-type devices, because they basically turn electricity into heat in a very spiky, pulsed way, in a very small volume. I cannot claim my belief is true, though, because I haven't verified it. I could simulate it to find out, but with the practical experience and anecdotal "evidence" on the matter, I don't think it is worth the effort.

author: Siwastaja
author_rank: Super Contributor
timestamp: September 12, 2020, 02:27:32 pm
content: Do note that gluing a bunch of heatsink on randomly chosen ICs on an SBC also increase the total cooling area of the whole SBC; even if those particular ICs generate fairly little heat and are OK with that, heat generated in other parts (most significantly, the main SoC) flows through any other IC, as well. Not to a great extent, but it could matter in the edge cases. And the SBCs tend to be designed to be marginal.Using high thermal conductivity gap pad (say, one of those exceeding 10 W/mK) to mount an SBC-sized large heatsink on the bottom side would likely do even better because of much more area, even if the pad needs to be quite thick (and soft) to account for component thickness. Alternatively, two layers of gap pad could be used, one cut around thicker components, touching the PCB, and another layer uncut.

author: Nominal Animal
author_rank: Super Contributor
timestamp: September 12, 2020, 03:49:58 pm
content: I do agree with Mechatrommer and Siwastaja above, in case I fail English again; just pointing out that I suspect that there is that odd corner case where those small heatsinks can make a big difference in stability for SBCs and graphics cards, even when not really doing that much to decrease the average temperature of the IC.Circling back to the original topic:I do like the two-sided sandwich-type aftermarket heatsinks for passive cooling of graphics cards (assuming sufficient airflow otherwise in the enclosure). The orientation of the graphics card does make this a bit difficult in many cases, especially larger cards almost compartmentalizing the enclosure. OP (13hm13) has a half-height card, which helps a lot. I personally would consider adding a low-RPM 120mm fan inside the enclosure for ensuring good air mixing – something that does not produce that much airflow, but ensures enough turbulence everywhere so that you won't get pockets of still/rotating-in-place hot air. I've also used thin foam baffles (packing material type, with melting temperature over boiling point of water) in a dual role: to divert air, and to absorb some of the noise.For SBCs, I've been looking at aluminium enclosures that are big enough to accommodate both the SBC and the connectors, with just the wires poking out (via split rubber/silicone grommets in the lid/box seam), and the enclosure itself acting as the heatsink. The ones I've seen for sale tend to have holes for the connectors instead, which defeats the purpose – a dust/water resistant enclosure for a shop environment, say a CNC machine server or similar. It does mean that to connect or disconnect a cable (USB, display, whatever) one must open the enclosure, but when closed, it would be basically dust-proof.

author: paulca
author_rank: Super Contributor
timestamp: September 13, 2020, 12:35:38 pm
content: On the dust problem. Putting thought into your air flow design and fan location and direction is not just about cooling. Its about dust management and sound levels also.ALL intakes should have dust screens. Exhausts, ideally should not.There should be more intake air flow than exhaust airflow. This means that air will be leaving through all the little gaps and vents instead of being sucked in there, where there are no filters.Cable management has become 1000 times easier in recent years as there are now usually PSU basements and side galleries to run cables easily. If you are a pedant you can hide almost every single cable neatly out of side... or use a boutique cable set to make a feature out of them.However. That GPU is punny. Doing anything to improve it would be putting perfume on a pig. It's extremely unlikely you will achieve an idle running temperature of less than 30/35*C with an air cooler. (With a large water cooler system, 12 fans and a beast of a GPU overclocked, mine idles about +10C ambient after it's been on an hour or more). More realistically 40*C idle on air. If you are using it just for desktop/office work, I wouldn't bother with even cleaning it out.Most GPUs that have boost clocks will give max boost up to about 60*C, then they will start to migrate back to stock clock speeds which they will hold until 85*C when they start to throttle back heavily and may lock up at 105*C with the die thermal cutoff. Running it at 85*C 16 hours a day will not damage it. It's been designed to be in a gamer PC and absolutely thrashed all day playing AAA titles.If it's having a relaxing retirement as a desktop PC now, it's living a life of luxury and will run forever, probably without the fan if you get a bigger sink on it.

author: paulca
author_rank: Super Contributor
timestamp: September 13, 2020, 12:42:20 pm
content: The attached still worked. Still gamed. It did start to thermal on me when pushed hard, hence cleaning it out. It was 8 years old, run and gamed every day, never cleaned (obviously).The second attachment is my more grown up approach today.