I have an ATX POWER SUPPLY UNIT that my DELL computer rejects as its not DELL? - Page 1
Forum section: electronics / projects

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 13, 2010, 10:05:12 pm
content: Hi Gang, okay I have this broken Dell Computer Tower, I have replaced the PSU with an ATX standard nothing powers up, only the little green LED Light on the Motherboard? I tried taking the CMOS battery out and made sure the connectors are in the correct hole etc.. still no powerI was told DELL only allowed dell components to fit in their machines and other makes were not compatible with dell, is they a way to tinker with the connectors to make the computer work? Obviously withoutblowing out the motherboard assuming its not already friedThanks everyone

author: fsleeman
author_rank: Regular Contributor
timestamp: March 13, 2010, 11:16:36 pm
content: First thing to check is if the motherboard has a 4-pin +12V input on the motherboard. If that is not powered up, the motherboard will not turn on. Its also important to know if the PSU is compatible with that kind of motherboard. Intel and AMD based motherboards often have an extra, and different, power input.Its unlikely that you will destroy your motherboard with a non-Dell PSU. These motherboard power inputs are pretty standard and hopefully Dell hasn't strayed to far. If the plug fits, its probably OK but to be sure you can always look at the motherboard manual and check the correct voltage at each pin and compare that to the PSU specs.Worse case you can always make your own molex connectors (probably molex) with the correct pin configuration unless the motherboard needs voltages not provided by the PSU, like -5V or -12V.

author: Murphy
author_rank: Regular Contributor
timestamp: March 14, 2010, 12:00:47 am
content: How old is the computer? I have a really old Compaq around somewhere the pins on the motherboard connector were completely scrambled. Can't imagine Dell doing something that evil these days though.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 12:07:33 am
content: Quote from: fsleeman on March 13, 2010, 11:16:36 pmThanks buddy, the computer was given to me free, it was not working but brand new, it looks mint, the capacators and everything seems to be fine, just no power. I dont have any manuals either. I still have my dell psu that I took out from it with the connectors, it dosent work however but the FSX PSU fits in the connectors but not powering up, only turning on the green LED on the MOBO

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 12:08:54 am
content: Quote from: Murphy on March 14, 2010, 12:00:47 amIts about 2004, beleive me search dell properetiey right psu and many people got screwed because they could not afford dell compatible components, so if you got a dell make sure nothing gets damaged otherwise you will have problems with the machine

author: fsleeman
author_rank: Regular Contributor
timestamp: March 14, 2010, 12:54:33 am
content: I am sure if you google your computer model you can find the manual online. If the necessary voltages are present in the PSU I am pretty sure you could rewire the power connectors if you wanted to go through the effort, although this might require making a new connector. Do you have access to another Dell PSU to test if the motherboard is working? What kind of PSU are you trying to use? If you cannot make all of the necessary connections to the motherboard I would be surprised if you see anything more than an LED working. You also might want to test the voltages on the PSU to make sure they are correct and stable.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 12:34:01 pm
content: Quote from: fsleeman on March 14, 2010, 12:54:33 amThanks Fsleemanhow do I rewire the power connectors? they all fit in perfectly in the motherboard. I can use the old connector from the PSU I presumeI dont have access to another dell but I was told if the MOBO was dead you would get no green light on. Im using a standard FSX 300 and the dell psu was a 250 power.

author: fsleeman
author_rank: Regular Contributor
timestamp: March 14, 2010, 07:02:37 pm
content: You can rewire the connected but doing exactly that, reconnecting the wires. It might be possible to back the pins out of the plastic connector and reinsert them into other slots. If the pins are crimped in you would have to either get a new plastic header and re-crimp the pins or cut the wires and solder them again. If you were to solder them again you would have to make sure they are done well with heat shrink tubing because these carry high current.Chances are that you won't have to do this. Are you 100% sure there are no power inputs on the motherboard missing connections? Before you start changing the wiring I would very strongly recommend you find the manual online and verify what inputs the motherboard needs, which voltages are supposed to be on each pin, and that the output voltages of the PSU is correct. Also, sending incorrect voltages to your motherboard will almost certainty destroy it.What is an FSX 300? An internet search does not show up anything relevant to this discussion.

author: djsb
author_rank: Super Contributor
timestamp: March 14, 2010, 08:22:57 pm
content: Hi,Do the wire colours on your OLD power supply conform to the ATX standard as detailed here?http://en.wikipedia.org/wiki/ATXIf so, the plug does not need rewireing.If they DO NOT conform to the ATX colours you may have to check on Dells support pages. This is mentioned in the link above.The POWER ON wire is pulled low by the motherboard and then there has to be a POWER GOOD signal coming from the power supply (the grey wire on the connector) otherwise the motherboard will not power up. This is also explained in the above link.Do you have the wires from the front panel connected to the appropriate points on the motherboard. The on/off switch in particular needs to be connected properly for the board to power up.I would recommend trying your best to get a manual for the motherboard (or post the details here so we can help). Please do not try to rewire the plug as you may cause more problems.HTH,David.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 09:49:28 pm
content: Quote from: fsleeman on March 14, 2010, 07:02:37 pmMy mistake the PSU is an ATX 300, it says Casecom on the PSU, The initall dell PSU was a 250W. Im quite certain that the green led when I power the unit on means the MOBO is not dead. The MOBO only has 2 connectors that the PSU connectors can go to on the actual board, one being the yellow and black 4 connector wire and the other the main strip connector with multiple pins, I dont know where the 4 pin connector on the PSU with red and black wires go to is has a black arrow on it? But my motherboard only has and had 2 connectors from PSU to motherboard on the original PSU and this current one.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 10:37:29 pm
content: Quote from: djsb on March 14, 2010, 08:22:57 pmHi David thanks for that link, yes my dell power supply the original and the current ATX im now using to try and get it to work are different the wires are jumbled up differently. The front panel wires and everything else is connected normal and is untouched. On my old dell power supply the yellow wire is first in the block and opposite is pink and red together in one square. on the last end of the block of the main big connector is Orange and Purple with Orange in the opposite. The Motherboard says Dell A00. Its a dimension 1100

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 10:39:15 pm
content: Quote from: djsb on March 14, 2010, 08:22:57 pmWhat I find strange David is on my dell psu they is a PINK wire on the main connector where as my ATX has no pink wire going to it? what is this all about

author: djsb
author_rank: Super Contributor
timestamp: March 14, 2010, 10:47:18 pm
content: Hi,Link for official service manual is here.http://support.dell.com/support/edocs/systems/dim1100/EN/index.htmHere is a link to the board usedhttp://www.intel.com/support/motherboards/desktop/D865GVHZ/index.htmand manualhttp://www.intel.com/support/motherboards/desktop/d865gvhz/sb/cs-010872.htmPower connections and board layout herehttp://support.dell.com/support/edocs/systems/dim1100/en/SM/techov.htm#wp1053452You'll have to check that the motherboard is indeed an 865gv using the information in the links above and by looking on the board for any identifying numbers.Then you need to identify if your REPLACEMENT power supply matches the ATX colour code. Identify if there are 5v rails,12v rails and signal wires on your power supply that match up to what the motherboard requires. You need to download wiring info for your power supply as well to confirm this.That's all I can do.Good luck.David

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 14, 2010, 11:16:28 pm
content: Quote from: djsb on March 14, 2010, 10:47:18 pmHiDavid, thanks I will have a look at that tomorrow, my eyes are hurting looking at those connector wires Why did they jumble them up like that, I was really happy when I received this computer and looking forward to getting it running to give to a friend who cannot afford one, looks like I learnt a thing or two but If I knew I would have not purchased the PSUThanks I appreciate

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 15, 2010, 09:34:27 am
content: Quote from: djsb on March 14, 2010, 10:47:18 pmDavid on my 20 PIN Connector on my ATX 300 PSU I have a white wire with a grey wire opposite on the connector, on my dell psu that blew out I noticed no white wire on the connector but instead a pink wire on the last hole of the connector with a red wire and opposite a Yellow wire. Plus on the Dell PSU that blew out I have a brown wire at the start of the connector in the same hole as an Orange wire and Opposite an Orange wire in the hole. My ATX has no brown wire on the connector?

author: Emyr
author_rank: Contributor
timestamp: March 15, 2010, 12:00:26 pm
content: If yours has an extra square 4-pin connector it may be because Intel boards use a 24 pin strip, and PSU makers use a 20 + a 4 next to each other to achieve this. the arrow probably shows which way it should fit next to the 20.

author: fsleeman
author_rank: Regular Contributor
timestamp: March 15, 2010, 01:10:56 pm
content: Look at this manual page (http://support.dell.com/support/edocs/systems/dim1100/en/SM/techov.htm#wp1053452) shows that your motherboard takes a 20-pin power inputPLUSthe 4-Pin power input. Make sureBOTHare plugged in. If that is done, the next step is the probe the output pins on the PSU to make sure they match to the voltages the motherboard expects. Even if the less commonly used wire colors (i.e. blue, purple) don't seem to match, what really matters is the voltages. The standard colors: red, orange, yellow, black, green should be 5, 3.3, 12, GND, PSU ON if I am not mistaken.To probe the PSU without connecting it to the motherboard you will have to short the PS_ON (green) to GND (black) to enable the PSU. At this point the fan (if one is present) should be on and voltages should also be available on the pins. It looks like PS_ONshouldbe pin 14 on the power connector.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 16, 2010, 11:10:14 pm
content: Quote from: Emyr on March 15, 2010, 12:00:26 pmHi Yes my ATX 300 has an extra 4 pin square strip block with red and black wires with an arrow, I ignore this cable and just plug the yellow and red 4 block with the main 20 pin connector on the Motherboard.I seen this video, I want to short the green wire and black with a paperclip or wire to see if the PSU is working, its a brandnew but is they any way to test the motherboard to see if it works? I get a green LED light on the MOBOthe above link is a video but on my ATX 300 I have no pink cable on my 20 pin connector, on my DELL PSU 250W That blew out it had a pink cable, other than that the connectors are the same

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 16, 2010, 11:13:46 pm
content: Quote from: fsleeman on March 15, 2010, 01:10:56 pmIs the 4 pin power output the yellow and black 4 block square connector? I also have a 4 block black and red connector with an arrow, nevertheless I tried both connectors, I tried every sequence and still I dont get any power, I just get the green led solid light on the MOBO when then 20 pin and 4 pin yellow/black is connected. I will short the green and black and let you know what happens

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 16, 2010, 11:33:48 pm
content: Quote from: fsleeman on March 15, 2010, 01:10:56 pmI just did what you suggested I poked a piece of wire to the green wire and the black wire on the PSU and pluged it in and switched it on and the PSU seems to be fine, this was when it was not connected to anything. Now how do I get this to work when pluged into the Motherboard is another challenge

author: fsleeman
author_rank: Regular Contributor
timestamp: March 17, 2010, 02:36:59 pm
content: The power button for the computer completes the short between the green and black pins and therefore turns the computer on. Did you check the voltages on the PSU? Just because the fan turns on does not mean everything is working, although it probably is.Quote from: VladKEasternTiger on March 16, 2010, 11:13:46 pmYes, you should have the 20-pin and 4-pin (yellow and black) connected to the motherboard. Are you sure that the power button is properly connected to the motherboard? There is braided 2-wire cable going from the power button to the motherboard. This actually enables the PSU and turns on the computer. If this is not connected or in the wrong spot the computer will not turn on. This should be covered in the manual.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 17, 2010, 09:57:22 pm
content: Yes, you should have the 20-pin and 4-pin (yellow and black) connected to the motherboard. Are you sure that the power button is properly connected to the motherboard? There is braided 2-wire cable going from the power button to the motherboard. This actually enables the PSU and turns on the computer. If this is not connected or in the wrong spot the computer will not turn on. This should be covered in the manual.Hi, Yes everything is connected well and the 4 pin connector gives a click, yes the power button is connected to a small bunch of thin wires with pins to the board, this has not been touched, the tower is new and has not been opened apart to get the old hard drive out from the previous userEverything is connected the right way, this is very strange

author: fsleeman
author_rank: Regular Contributor
timestamp: March 19, 2010, 05:02:27 pm
content: If indeed everything is correctly plugged in (especially the power button), it sounds like either the PSU or the motherboard is broken. Testing the voltages on the pins on the PSU is the simple way to do. Has this computer ever turned on before? Why are trying to replace the PSU, do you think its broken? Bad voltages from a broken PSU could damage the motherboard which might explain your problem.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 19, 2010, 07:05:50 pm
content: Quote from: fsleeman on March 19, 2010, 05:02:27 pmThe dell PSU was definentely broken as it never powered on, and no led light on the motherboard lit, when I purchased a new ATX 300 the led on the MOBO Lights up but nothing more. I will try and see if they is a way to bypass the switch and go directly to the MOBO pins to see if I can switch it on

author: Unknown
author_rank: Unknown
timestamp: March 20, 2010, 02:56:40 am
content: Easiest way I have found to fix this problem is to plug PSU into MB, hit front switch, if it does not power up use a length of solder and carefully short (on the PSU connector) PS_ON (Green wire on ATX standard colour code) to GND (Black wire on ATX standard colour code). If it now runs, then it is a faulty switch or motherboard. If motherboard, you may be able to try a couple of different ideas:#1 just switch PSU on / off with manual toggle switch (making sure OS is halted (*nix) or shutdown (windows))#2 use manual switch in conjunction with mb switch (the Motherboard switch my still work in software (ie suspend / power options) just no physically toggle the PS_ON output

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 21, 2010, 03:10:52 pm
content: Hi, I connected a small piece of wire to the green wire and black wire and pushed the main connector in the motherboard so it fits in, I CONNECTED the other 4 block connector and turned on the PSU from its switch on the casing, and I have power to the Motherbord, the fans run on the board, the 2 lights are on on the leds at the front of the unit, I heard 1 beep sound when I turned it on for the first time, the problem is Nothing on the MonitorNothing on the keyboard no lights, nothing and when I pressed the power button on the unit and hold it nothing happens because I shorted the green/black wireSo what next?You all been a great help for theseideas

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 21, 2010, 03:16:50 pm
content: Im also wondering if I can boot up the pc without a hard drive installed because the hard drive I connected to the motherboard was from another machine, so I got 1 beep when I turned it on for the first time, I get 2 led lights on the front of he unit and the fan runs on the MOBO. Nothing on the screen its not recognising a monitor or keyboard

author: embedded
author_rank: Newbie
timestamp: March 21, 2010, 10:56:03 pm
content: As Long as ALL the BIOS is in a chip you can boot without a hard drive. You will just get to a no disk prompt unless you hit F2, DEL or other method of entry into the BIOS.If you can boot from CD/DVD please consider booting "System rescue CD". A very useful Linux based CD with rescue tools.http://www.sysresccd.orgI tend to use this or Clonezilla all the time for preparing, cloning and fixing hard drives.Please note the extensive documentation on the page. In the mid 90's HP and Compaq put some of the bios on the disk to save money but these units can not boot a CD. (The first 286 AT's had the bios setup menu on a floppy.) Since then the all in one standard BIOS has been the norm.If the actual motherboard, CPU or RAM are bad rescueCD will fail mid way. Never try and fix a Hard drive with a dicey motherboard.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 22, 2010, 12:06:35 am
content: Hi Embedded, thanks for your reply, im tired and gonna hit the bed its 20 past miidnight zzzzzzzzwhen I turn the PSU Switch I get the fans running on the MOBO, disc drive opens, the lights on the mobo and led at the front light up, only nothing on the screen, my computeris not recognising my monitor? yellow light on monitorno recognition

author: fsleeman
author_rank: Regular Contributor
timestamp: March 22, 2010, 01:14:50 pm
content: What kind of monitor do you have? Is your video card built into the motherboard or is it a stand alone card? I would try an different video card if you have available. I have gotten a motherboard before that had a bad PCI-e slot but the integrated video worked, so its good to check everything.

author: djsb
author_rank: Super Contributor
timestamp: March 22, 2010, 11:31:06 pm
content: Hi,Have you got any RAM installed?David.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 23, 2010, 09:48:40 pm
content: Quote from: djsb on March 22, 2010, 11:31:06 pmHi David, yes I have 2 sticks of the original ram installed, I then did different combinations of taking one ram out and starting the pc, I also took out the CMOS battery, still nothing on the screen

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: March 23, 2010, 09:59:44 pm
content: Quote from: fsleeman on March 22, 2010, 01:14:50 pmHi on this Dell pc the video card is built into the Motherboard, on my other pc which is old the video card is separate with a heatsink on it, It looks like I will have to try another video card but the question is how if it is built in the MOBO? The monitor connector on the unit is connected directly to the mobo.

author: djsb
author_rank: Super Contributor
timestamp: March 24, 2010, 08:57:59 am
content: Hi,1/ Check the motherboard for a jumper that turns on/off the integrated graphics (information in manual link given earlier).2/ Turn off the integrated graphics card and insert a card in a PCI slot (if available).3/ Also remove and replace memory chips just to make sure connections are secure.David.

author: fsleeman
author_rank: Regular Contributor
timestamp: March 24, 2010, 02:36:56 pm
content: Is the internal PC speaker connected and do you hear any beeps?You might want to just plug in a PCI-e video card and see what happens. Many motherboards will default to the PCI-e card if there is one present without changing the BIOS or jumpers.

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: April 07, 2010, 08:47:14 pm
content: Hi Finally I get the Computer working thanks to you, and the others, My friend just gave me a DELL Power supply unit and boom it worked, so simple but these silly companies like to use proprietary components. Once again let me take this opportunity to thank you flseeman and the othersThanks

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: April 08, 2010, 07:02:47 pm
content: It begs the question then... What's in the Dell psu that allows it to work when other ones do not?

author: VladKEasternTiger
author_rank: Regular Contributor
timestamp: May 05, 2010, 10:28:18 pm
content: Quote from: Ed.Kloonk on April 08, 2010, 07:02:47 pmThats the 64k dollar question my friend, if anyone knows even thoe Im glad to see the back of that dell tower id still be interested to know why, as for dell well they have lost me as a customer for good how dare they only use proprietary parts for their equipment

author: Pyr0Beast
author_rank: Contributor
timestamp: May 06, 2010, 10:48:51 am
content: You could start by measuring voltage when on and when off on the ATX connector.Some PC's (esp. Compaq's) had PS-ON signal inverted - PSU was turned on when there was 5V on PS-ON pin, different from usual ATX PSU's where they turn on with PS-ON pin at 0V.

author: fsleeman
author_rank: Regular Contributor
timestamp: May 08, 2010, 05:09:41 pm
content: Quote from: Ed.Kloonk on April 08, 2010, 07:02:47 pmMost likely they have a different pin outs. Checking the voltages would certainly work and comparing wire colors (as long as they are still standard) could work too.