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Pc turns on for a split second and shutsdown

  • Motherboards
Last response: in Motherboards
June 13, 2011 3:47:38 PM

Hello all,
I will be checking this again tomorrow.

Asus Z8PE-D18 = motherboard

Lian Li PC-2120B, Black Aluminum = Case

1200W Antec High Current Pro 80Plus = PSU

Nivida quadro 4000 = GPU

1x Xeon 5690 = CPU

don't think anything else matters anyway Problem is i turn the computer on the fans spin once around and then it shuts down THIS IS A NEW BUILD AND FIRST TURN ON. just wondering whether i havnt plugged something in correct of missing i have check with my colleges and all the wiring SEEMS correct i have the 24/8/8 pin in.

is there something which is a regular problem with these components or a common fault on new builds?

again i will be checking on this tomorrow so sorry for late reply

Thank you for any help you give much appreciated

More about : turns split shutsdown

a b V Motherboard
June 13, 2011 4:56:26 PM

This screams memory issue -- either bad memory or bad seating of the memory. A few recommendations:

1) Remove all except one stick of memory and determine whether it will boot on one-stick-at-a-time. If that stick doesn't work, switch to the next and boot with it on it's own.

2) Ensure that RAM is inserted fully and firmly into the slot

Does that do anything for you?
a b V Motherboard
June 13, 2011 6:39:01 PM

Indeed, sounds a bit like a RAM issue.

Also, does the computer cycle back on after it shuts off?
Related resources
June 13, 2011 7:05:27 PM

Ok i will try this tomorrow as i am out of work atm i will inform if it doesnt work and no it doesnt turn back on
June 14, 2011 8:21:54 AM

ok i tried all the memory nothing worked it still does the same the fans spin once and turns off but the green light on the motherboard is still on

Plus the lights on the front do not light up and i have done the led light cables correct
a c 156 V Motherboard
June 14, 2011 3:00:59 PM

Doomsword, he can't run memtest. The system doesn't boot.

Turn on and immediate shutdown is not a typical RAM problem.

Time for some serious troubleshooting.

Work systematically through our standard checklist and troubleshooting thread:
I mean work through, not just read over it. We spent a lot of time on this. It should find most of the problems.

If not, continue.
The following is an expansion of my troubleshooting tips in the breadboarding link in the "Cannot boot" thread.

I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different, but they all use a single short beep for a successful POST.

Breadboard - that will help isolate any kind of case problem you might have.

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.

Make sure you plug the CPU power cable in. The system will not boot without it.

I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.

You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.

If no beeps:
Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.

At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.

A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.

This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

If the system beeps:
If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.

Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.

Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST.
At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.

Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
June 14, 2011 8:14:04 PM

I have sorted the problem out turn out to be the spacers under the motherboard there were to many and the ones that were not needed were interfering with the motherboard circuit hope this helps other people when building their new builds
a b V Motherboard
June 14, 2011 8:53:18 PM

Interesting. Always good to breadboard before a build or when all else fails -- those kind of issues can be ruled out with that sort of testing.

Motherboards are rarely just plain bad.