PC turns off quickly when powered on


I'm building a new PC and I've put together part of it. I read that it's a good idea to do a power test before you have everything in place so that problems will be easier to troubleshoot and to save some work if things aren't working. Right now I am running the following:

XIGMATEK HDT-S1283 120mm Rifle CPU Cooler

GIGABYTE GA-X48-DS4 LGA 775 Intel X48 ATX Intel Motherboard

ABS Tagan BZ Series BZ800 800W ATX12V / EPS12V Patent Piperock Modular Power Supply

A-DATA 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model ADQVE1B16K - Retail

Intel Core 2 Duo E8500 Wolfdale 3.16GHz LGA 775 65W Dual-Core Processor Model BX80570E8500 - Retail

all of this is in a NZXT Tempest case.

The case cables (power, reset, 2xUSB, eSATA, HD audio, hdd led) are connected to the mobo. (side question - if the mobo manual says nothing about which sata port to connect an eSATA cable to, does it matter?) The 24pin and 8pin power cables are connected to the mobo, and the heatsink fan is connected to the cpu fan connector on the mobo. I also have one case fan and one case LED connected to the psu.

When I press power after turning on the psu, everything lights up and the fans start moving for about a half second, and then everything turns off. If I press power again, nothing happens. If I turn off the psu, and then press power again, the pc turns on for a half second again. (there are never any beeps)

My questions are:

Should I be performing a power test at this point in the build?
Is the fact that it turns off after a half second a bad thing or could it be caused by the fact that I haven't installed the other components yet?
Do you have any ideas why this is happening and/or what I can do to fix it?

Thanks for any comments :)
6 answers Last reply
More about turns quickly powered
  1. Finish the build. Be sure to reset the cmos after you actually have all the parts.
  2. Well with those parts the computer should at least be able to perform a POST, so no its not a good thing.

    I would take it all apart again, especially check that the processor is seated correctly. Make sure no metal parts of the heatsink are touching parts of the motherboard that they shouldn't be.

    Check all your connections again, power, sata, etc.

    Hope you figure it out.
  3. It's your Ram, take one stick out and test the system, then try the other stick to figure out which stick is bad.
  4. You probably have a case speaker header somewhere on the board that you can wire a small speaker into. This will give you beeps.

    It's quite common for a board to misread RAM and so not supply the correct settings to post, or as mentioned for one of the sticks to be bad. If you can boot with one stick check the settings right away before trying the other.

    Also be sure that ALL your motherboard power connections are made.
  5. Thanks for all the quick replies.

    I tried the RAM, but the same thing happens with both sticks individually and with both at the same time. One thing I just checked was my motherboard ram compatibility list: http://www.gigabyte.com.tw/FileList/MemorySupport/motherboard_memory_ga-x48-ds4_1.3.pdf

    I don't see my exact model of ram on there, could this be a problem or is this just a list of the specific models that they have tested (and there are other models that work with this mobo)?

    Now I'm proceeding to recheck all connections. After that, I have one suggestion to take everything apart and one suggestion to finish the build :S I'm not sure which to try first.

    Thanks again
  6. OK, problem solved... It wasn't actually a problem. I put in the graphics card and now it works fine. Now I feel dumb for wasting two hours trying to figure this out :) I guess the mobo or psu needed to be connected to a graphics card? Either way, thanks for your time and help.
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