New build no power!! help!

I recently put this system together:

Gigabyte GA-965P-DS3
Corsair XMS2 DDR2 667
Coolermaster Centurion 5 case
OCZ modstream 520W EZmod Cables PS

On my first attempt at hooking it all up I connected teh 24-Pin power connector, 4-pin 12V powered on but there was no video. Fans were spinning everything seemed normal but no video. I did some trouble shooting took out one stick of ram...left in the other, reseated the vid card. Still no video. I removed the MB and checked the CPU connected to heatsink it all looked ok so I put it all back together, now when I try to power it on nothing happens!

Any suggestions?
32 answers Last reply
More about build power help
  1. There is 120V AC going to the PS so that is fine.....
  2. Oh ya , also on the first build attempt when it powered on...I removed all the memory to see if it would beep for me but all i heard was a distorted "scratchy" sound from the it was trying to beep but was all distorted....I replaced that speaker and it did the same thing
  3. Well assuming that you have tried alot of trouble shooting and double checked all of your connections, 24/4/molex/and 6pin, and everything is seated correctly id start shooting through every part, first and for most the psu. If you have a 2nd computer to test it on(assuming you do), you can:
    1) disconnect 20/24 pin and 4/8 pin from old comp, and just plug in the new psu and test to see if it works. If it does mark that one off.
    Post back with progress!


    techspert since i was 8, just new to these forms and have build several differnt computers from the 533hz socket a up to the pd 775! dont let my newness slant your view
  4. Ya I wish I could troubleshoot with another system but I dont have one available...its really strange that it powered on before but now it doesnt after simply removing the MB and then reinstalling it..... I looked over all the connections and I cant think of what it could be!

    I figured maybe the PS wasnt getting enough of a load (I heard it wouldn't start because of that) so I connected some drives to it but still nothing..tried reversing the polarity on the Power SW connection to MB and tried the power switch in combonation with the PS switch still nothing!!

    This is so frustrating!
  5. Does the Video card have a molex connector? Make sure it's connected.

    If you have a multimeter check the voltage of the 12 and 5 volt rails. This is hard if it wont boot!!

    Sometimes when you push the large power connector into the motherboard some of the pins can be pushed up instead of seating correctly. This will cause an intermittent power fault.

    Scratchy sound from the speaker could be a bad motherboard as the beep is coming from the power on self test in bios. Could also be intermittent power fault.

    Try another powersupply first. Just because it's got 120v going in doesnt mean its got power coming out.

    If the input voltage is switchable on the back make sure its not set at 240volts.
  6. Yes the PCI-E power connection to the vid card is connected, the switch on the PS is set to 115V (north america)

    Yes I have a digital multimeter but im not really sure where/what to measure im looking into this now...but how can I measure anything comming out of the PS if it will not turn on.....

    Checked the Pins on the 24 pin connector...looks fine connection is good
    4-Pin pins are fine connection is good

    Im thinking its something with the Power Supply because when it did get power everything seemed fine...the motherboard was powering all devices the only thing that makes me thing MB would be the distorted sound from the speaker but now since the PS does not turn on im starting to think its the PS

    Though I dont really want to buy another PS just to test this theory....
  7. Well I will not point fingers at which component is bad, but we need to get over the psu hump before we solve anything, if the psu is faulty then I'd suggest replacing it. The easiest way will to use Bestbuy as your alternative, and thier 30 day garuntee to get you over the hump of waiting for rma. Mind you this will only solve the problem if its only your psu. And yea a faulty psu can work at first, then crap out. Ive had it happen on me before...pain in the neck. I know of a way to actually power on the psu with out hooking it to the mb, but have a meeting togo to for the next 1.5 hours. Ill write back soon if someone else hasnt helped. BB psus are about 40-120$ but you can always take it back(unless dmged).

    Be back l8r,

  8. To do a quick check of the power supply get out your handy multimeter and a spare piece of small wire. Next Jumper the green wire on the powesupply cable that goes to the motherboard (20/24 pin connector) to a ground in the same connector (any black wire next to the green one) That will force the power supply turn on. Next grab the multimeter. Main ones to check is the Yellow (+12v) Red (+5v) and orange should be +3v but i dont remember exactly, but the main yellow and red should give the proper voltages. Do all of this testing with it disconnected from the mother board assuming that it is not bad. Try that and report back, also you can conect a DVD drive or something (fan, lights) to see if the power supply is coming on when jumpered. Yea the psu fan should spin too when jumpered.

    If you find the psu checks out and it still dosent turn on the MB when the power button is pressed , its more than likely the MB or sometimes, but rarely the processor,
  9. It is going to be really hard to diagnose without another system or spare parts.

    One thing that you can check though is the PSU. Follow the instructions to try it.

    P.S. Is your set up in the case or are you testing it un assembled ?
  10. Disconnected Power leads to MB and jumpered Green to Gnd, turned it on and it fired up!

    +12V line is good
    +5V line is Good
    +3.3V I think it was is good

    PS seems to be working fine
  11. damm you beat me to it :evil:
  12. try is with just the MB and cpu. c if it powers up.
  13. Well where did you get your motherboard? Do they have good customer service? I know i have had problems in the past with Ati videocards doing exactly what problems you are having (not ati bashing or anything) But that was a rare problem. Id say if you cant get any other motherboards or computers to test the rest of your stuff on get the Mobo RMA'ed and go from there, its either that or you have Case issues with the power button faulty or the mother board is grounding out somehow. But to test the power button you can swap out the jumper from the reset switch and hit the reset switch to try to turn it on. Just a thought these kinda problems keep me up at night when i have em, good luck
  14. Ok, well meeting cancelled... so i got a free sec. Ok so now that you know the psu is good have you checked the power switch itself? I know it might sound lame but it is something ive run into before. Disconnect the little PWSWITCH plug from the mother board, and then use the voltmeter, set it to act as a battery(if it has the capability) and then check to see if you get voltage, or of your actual leads to the switch(meaning the back of the switch itself) is accessable test those, some cases are easy to get to. So psu is good, thats great - now the fun begins!


    Edit: I didnt put in here and i assume that you know to toggle the switch... just trying to cover all of it.
    2nd Edit: If my memory serves me I believe you need to check resistance, im no electrical engineer...and unfortunately aerospace engineers dont focus on this :( Sorry if my electrical lingo isnt up to par.
  15. If you know that the PSU is working fine, then I would really take a look at that CPU again. Problems with the CPU recognition can lead to initial fans working, without screen, and then eventually even present as a non working computer.

    I don't think that your new CPU is broken, but maybe it is seated incorrectly?

    The odds are against your new memory being bad. Most of the time these power failures are not faulty parts, instead they are due to misconnections, or BIOS changes.

    I checked your board info, and you shouldn't have a problem with the 6600 on it from the get-go. The F1 version of the BIOS supports your new chip, and your board should have shipped with at least that.

    I know it sounds kinda stupid, but usually it is the simplest things that mess up a build. We then spend money and get frustrated on advanced changes that really don't figure into the problem.
  16. I unplugged the PW Switch from the MB and put the Reset switch in its place... still no power

    Ive reseated the CPU 2 times now so im almost positive that it is seated correctly... I had installation diagrams etc...

    Im thinking maybe the 12V 4-Pin connected that powers the CPU is not working correctly because I read in the manual that if it is unplugged the system would not start so I am gonna unplug the Power from the motherboard and short the Green to GND on the PS and measure the voltages on the 4-Pin 12V plug


    Okay so the 4-Pin 12V plug is fine
    So im at a loss....unless there is something going on with that power switch...I remember when it powered up the first time the power switch did not work but it still powered up. Had to use the PS switch to turn system off
  17. I Checked the CPU one more time just to make sure and its seated properly.

    System just simply will not power on
  18. If you are referring to the actual MB powerswitch connection, I believe that you can use either a paperclip, or head of a standard screwdriver to "jump" the powerswitch yourself. NOTE.. I am referring to the low voltage pins ON the motherboard that feeds to the power switch on the front of the case (the pins are next to the HD LED, PWR Reset pins).

    I have never done this myself. You may want to wait for a response from another person who has had success with it. Electronically, it is a sound theory.
  19. Ya i was thinking the same thing....shorting the two pins but i dunno if I wanna try it im kinda weary

    - I wish there was an LED on the MBD like ive had in the past...then I would know it at least has power to portions of it when the 24-Pin connector is in place

    - I might try a drop-kick to the CPU I heard that could help in these situations :wink:
  20. three0duster: I got all my parts from which is supposed to be very reliable

    choknuti: I disconnectd everything but the motherboard CPU/HS/FAN and still no power

    And I also just tried shorting the PW (Power switch) pins on the motherboard to rule out the Switch on the case from the problem and it still didnt power up

    These are what im using as standoffs for the motherboard (were included with it) these will not cause a short circuit right????

    I see a lot of other plastic ones?

    Also does the orientation of the heatsink onthe CPU matter?
  22. If you are only fitting the ones that correpond to a hole in the MB then you wont be shorting anything.

    Anyway it wont hurt to remove the mb from the case put it on a non conductive surface and try to power up.

    Unfortunately it looks like u'll have to check that CPU and motherboard with another system. :cry:


    And the orientation dosen't matter. Even if the HSF was not installed (something that you shouldn't try) the pc should power up.
  23. Im gonna try to get the motherboard replaced this just seems rediculous that it doesnt power up with just CPU and motherboard with power connected properly and powersupply works........... it's the only other thing I can think of at this point
  24. I think you are right, there is a chance that it is the CPU but I would check the MB first. Is there no way for you to test it? (another system or spare parts)
  25. Sorry for my long absence, work picked up hard core and just managed to get back on my home pc. So the PS switch is out... next lets see here, with the cpu off the mem out and nothing hooked to the psu ectept the MB do you still get any noises? This is looking like a faulty MB since weve canceled out the psu and case, and if you tried shorting out the PWSWITCH pins and still nada... then I would agree with a RMA of the MB. Hopefully this should fix your problems... other than that i dont think you want to order individual chips, and solder them thus voiding any warranty :-P. PM me if you need anything as I will be to busy to read fourms this weekend. Best of luck!

  26. before you ship anything back...

    i had a similar problem.

    ur ram prob isnt compatible out of the box with ur mobo.

    get some cheap ddr2 (try office depot, they have kingston which workd in my s3) boot that sucker up, change ram volatage to 1.9 2.0 or w/e volatge u need. then u should get it to post. after that return the cheap ram.

    worked for me!

    i had fans spinning but no video and id idnt expect it to be the ram, but it was!
  27. I would try that except that now the system does not even power on as apposed to it powering on with no video.... Right now there is no ram at all in the system just the CPU and Motherboard it wont powerup no matter what is in it, I also tried to turn it on outside of the case on a non conductive surface incase of shortcircuits but alas no luck.

    - Im gonna mess around with it this weekend since I cant send it back till monday anyways so if anyone has anymore suggestions please let me know

    - There is one "hole" for a standoff for the motherboard that is not being used anyone know if all standoffs must be screwed down? incase they are grounds or something?

    - Also, is there anyway to test a CPU without putting it in another system?
    - would the system power on with NO CPU in the motherboard as apposed to having a faulty CPU in there preventing it from starting?
  28. Hey, yea... just dont waste a good weekend on a faulty MB, as far as the stand offs they are not used for a ground so you do not have to have them down at all, infact some cases come with plastic stand offs.

    I wouldn't suggest messing with the CPU or memory until you get a new MB, since messing with the cpu is just a disasterous thought, and if the board wont budge with out mem, its prob not gonna work with mem.

    But yes the board should atleast make sounds with out a cpu installed if you have a speaker hooked up. One thing I havent asked is are you depending on the sound out put by the 3.5mm jack or the case speaker? J/w

  29. Quote:

    - Also, is there anyway to test a CPU without putting it in another system?

    Unfortunately the cheapest device to test a CPU is a MB :(


    - would the system power on with NO CPU in the motherboard as apposed to having a faulty CPU in there preventing it from starting?

    I haven't tried it but I should think not. The chance that it's your CPU is rather slim. (I would say less than 5%) While as in a MB there are so many things that could go wrong.
  30. Well I sent the MBD back and hopefully this fixes the problems

    its going to the other side of the country (From Ontario to BC) so the new one will take a while to come back

    It sucks that all these new parts are just gonna sit here for that long and collect dust but oh well thats life :?

    I'll let you guys know if this fixes the problem!

    Thank you everyone for the help
  31. good luck
  32. Yea.. sucks when a good thing goes wrong... Hopefully they will take care of you. Best of luck on the build and PM me if you get anything back.

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