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New PC Boots for 1/2 second, turns off

Discussion in 'Tech Support' started by Tsen, 20 Nov 2007.

  1. Tsen

    Tsen Steeped In Romance

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    Okay, I had another thread about this same PC dealing with a question about the PSU, but now I'm having a new problem.
    I've put the whole thing together, push the power button, and the fans barely start to turn and the whole thing turns off again. No idea what causes it--PSU is fine, connections are fine, motherboard isn't touching anything it could short on, I'm lost.
    What could cause that? Do I have a bad motherboard I ought to RMA?
    System specs are:
    Gigabyte GA-MA69GM-S2H Motherboard
    AMD Athlon FX X2 4800+ Processor
    2GB OCZ Platinum 800 mhz RAM (2x1GB)
    Rosewill RV350 350-watt PSU

    EDIT:
    Oh, and for the record, I have tried booting it with my 450 watt Antec PSU as well, and it still doesn't work. I know the Antec works because I'm using it in my gaming PC now, so it most likely isn't a power supply related problem.
     
    Last edited: 20 Nov 2007
  2. Chops

    Chops What's a Dremel?

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    I'm no expert, but I do have a suggestion. Make sure your ram is properly installed, this could be a cause.
     
  3. Tsen

    Tsen Steeped In Romance

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    I'll try again. RAM is one area I'm uncertain on--I've heard this motherboard is finnicky and requires 1.8v RAM. The Platinum runs fine at 1.8, but needs 2.1 to get the best CAS times. Anyway, I'm moderately sure that's not the problem, but better safe than sorry.
    Also going to try wiring the reset switch to the power header and see if it's just a problem with the case's switch (it's a cheap nMediaPC case, bought it for the looks not the quality).

    EDIT:
    Okay, so I didn't want to double-post.
    Checked the RAM. This time I was using some old PC-3200, which might be a problem, since the motherboard supports DDR2 only, and PC-3200 is the brink between DDR and DDR2. But it had the same problem when I tried with my PC-6400, so...
    Also, using the reset switch instead of power didn't help.
     
    Last edited: 20 Nov 2007
  4. cmberry20

    cmberry20 Mad Scientist

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    Some motherboards do this if you have the CMOS clear jumper set in the wrong position (eg. in the 'clear' position). I would make sure that this is ok.

    I know that you said that you checked for electric shorts etc, but I would remove every (And i mean EVERY) PSU feed expect for the 24 pin motherboard cable to the motherboard & try to power on. OK, the PC wont boot but if the fans start to spin you can slowly add the other PSU connectors one by one - turning the PC on each time - until you find the problem.

    btw - you cannot (its impossible & might possibly damage your motherboard) use DDR1 memory in a DDR2 motherboard unless it accepts both (some do - but they have independent slots for both types).
     
  5. Tsen

    Tsen Steeped In Romance

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    Okay, first off, it's a 20-pin PSU, not a 24. The MoBo is a 24 pin though. In the other thread earlier I learned that the extra 4 pins help with stability, but aren't necessary, especially with low-power draw systems (like this one). I thought that might have been the problem, so I used my 24-pin Antec, and no luck there either. As for the memory, I don't know if it's DDR1 or not. Like I said, PC-3200 is on the brink--they made both DDR1 and DDR2 versions of it, and I don't know what this is because it's no-name junk. Anyway, I'll keep testing with the DDR2 800 stuff and try the PSU connections like you said.

    EDIT:
    And...nothing.
    Unplugged everything but the 4-pin power and the 20-pin power, and still wouldn't do anything.
    Do I RMA the PSU, even though the Antec one didn't work either?
    Do I RMA the motherboard?
    Do I just return the whole shebang for the hell of it?
    I dunno. It's clear that something is defective, but I don't know what.

    EDIT #2:
    Tried the CMOS jumper too. Nothing there, either.
     
    Last edited: 20 Nov 2007
  6. Krikkit

    Krikkit All glory to the hypnotoad! Super Moderator

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    DDR won't fit into a DDR slot and visa-versa - they're completely different types and won't do either the slot or themselves any good in the wrong kind. :)

    I'd say this is RAM/CPU/Mobo troubles tbh, although I can't quite decide what. The mobo won't boot without RAM, graphics card and CPU (with cooler). Does the board have any diagnostic LED's? Those would be a big help.
     
  7. Hardware150

    Hardware150 Minimodder

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    Last time this happened to me was when i had a crappy case and the motherboard was shorting on the case, make sure it isn't shorting on the case anywere, try it without a case and see if that works (be careful if you do this tho)
     
  8. cmberry20

    cmberry20 Mad Scientist

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    ^ Agreed.

    A while back a friend had a similar problem & that was the USB header on the motherboard had shorted together (bent pins!!) thus wont let the PC turn on.

    You don't need a CPU, RAM or G.card for a PC to power up - it just wont boot/post. To eliminate everything - remove the motherboard from the case. Remove all your components - leave the CPU fan connected to the motherboard. Place your mobo on the box it came in (thus preventing short circuits). Now connect the 20pin PSU lead to the mobo. Don't bother with the 4 pin one. Try to power on. (you can short the two power switch pins on the motherboard with the end of a screwdriver - its perfectly safe).
    Does the cpu fan start?

    ^ Before all that, I would try another PSU.
     
  9. capnPedro

    capnPedro Hacker. Maker. Engineer.

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    Make sure the heatsink is properly seated on the CPU (try reapplying thermal paste and reseating it)

    Whenever this happens to me it's usually because the CPU is overheating and thermal protection kicks in to shutdown the PC.
     
  10. Tsen

    Tsen Steeped In Romance

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    I already tried another (definitely working) PSU. I won't rule out case troubles, this one's a dirt cheap one. Anyway, I don't think it's overheating, there just isn't enough time for it to get that hot. It's literally a fraction of a second. Anyway, off to try the mobo out of the case. Thanks for the help!
     
  11. Tsen

    Tsen Steeped In Romance

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    Okay, one step closer to a solution.
    The problem was the four pin secondary connector. When it's not connected, it powers up fine. No shorts at all, just that four pin. Wasn't the power supply, so I'm guessing either it's the motherboard, or I'm doing something wrong.
    It will turn on all the fans without the 12v 4-pin, but it won't post, just turn on and sit there with a blank monitor. WITH the 4-pin, it just does what it did before, turn on for less than half a second and turn off before the fans even really got moving.
     
    Last edited: 20 Nov 2007
  12. capnPedro

    capnPedro Hacker. Maker. Engineer.

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    Seriously it's overheating. 4 pin provides power to the CPU. It boots (but won't POST) without it because the CPU is not heating up or doing any work.
    And seriously, with no thermal paste a CPU will throttale after 0.5-1 second. That's all it takes.

    This has happened to me twice before. EXACT same circumstance/behavior. Did I mention I was super super serial?
     
  13. mansueto

    mansueto Too broke to mod

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    This happened to me, i thought it was my power supply because it was my first time sleaving and modding a power supply and i messed a few pins up, so i went and bought a nice new modular one and i had the same problem. Try taking the video card out and seeing if it boots up, it won't actually boot but it will stay on. If you put the video card back in, make sure you put it in properly so it seats properly. I made my pc, and i bought a crappy case that had warped my graphics card (radeon x850 pro) and when i put it into my new thermaltake armor case in the summer it wouldn't turn on. I tried everything and finally after taking the graphics card out it was a breakthrough. Once the card was seated properly it worked fine. I had to do a little filling so the card would seat properly but after that i've never had any problems with my pc. So to restate it all, take graphics card out, start it up, see what happens, if it stays on then your graphics card wasn't seated properly, if it stays off, it could be a loose connection or something different. To find out if its a bad power supply, try the same power supply on a different pc and see if it works.
     
  14. Shadowed_fury

    Shadowed_fury Minimodder

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    QFT, happened to me loads. So lapped CPU = win.
     
  15. chrisb2e9

    chrisb2e9 Dont do that...

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    a few people have suggested that it may be a short. since it happens when you plug the 4 pin power in I am inclined to agree. Even putting the screws in too tight can cause a short. Why not take the motherboard out, and put it back in(make sure to use the standoffs for the screws). are you running without a cooler for the cpu(dumb question i know but i have to make sure). if you have the cpu cooler on then it wont overheat in 1 to 2 seconds. especially since its not exactly under any load.
    someone else mentioned the cmos reset jumper, and making sure that its not set improperly, take a look at that and while you are at it why not reset the cmos just to make sure that something isn't going on in there.
     
  16. Krikkit

    Krikkit All glory to the hypnotoad! Super Moderator

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    Lapped CPU cooler = win, they're cheap to replace - lapped CPU = loss for most people because it's very difficult to get a decent, flat finish on the top without a machine.

    To be honest you won't get overheating if there's any kind of contact with the CPU in such a short time, especially from a cold boot (i.e. everything's at room temperature).
     
  17. Tsen

    Tsen Steeped In Romance

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    Okay, I checked the heatsink contact and thermal paste, and same problems. I KNOW it isn't a short because it does the same thing with the motherboard removed from the case entirely and set on top of the box--it will boot with the 20-pin, but not with the 20 and the 4 pin both.
    Also, it's running integrated graphics, so it isn't a problem with the gfx card not being set properly. Could I just have gotten broken hardware? A fried motherboard or something?
     
  18. Gumbatron

    Gumbatron What's a Dremel?

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    I'm thinking that this problem is due to an electrical short. Have you tried re-seating the CPU, checking for bent/broken pins (not likely, but) otherwise I'd have a really good look at the mobo around the cpu power mosfets etc. Look for anything that looks burnt.

    There is a possibility that this is heat related, but it sounds a little fast. If you were to send anything back for warranty, I'd vote for the Mobo

    Good luck
     
  19. cmberry20

    cmberry20 Mad Scientist

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    I think its possibly the mobo. If the main 20 pin is ok (PC turns on) but with the 4 pin plugged in it doesn't, that's telling me there's a short on the motherboard. And if you've tried another PSU - that rules that out.
     
  20. Tsen

    Tsen Steeped In Romance

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    Okay, I checked the processor. No bent pins, seated right and oriented correctly. In short, I have no clue what the problem is, so I'm just returning the motherboard to Newegg. Thanks for the help, I've never really had to diagnose hardware problems like this before.
     

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