PC starts up, then ~1 sec later shuts down. And repeats.Hi all, Have an issue with

Hi all,

Have an issue with my PC. When I press the power button, the machine whirs into life for just short of a second. Then dies. After a ~2 sec delay the process will repeat. This will continue until the PSU is switched off or the main supply removed.

I have removed all connections in an effort to identify where the issue is arising (HDD/GPU/RAM/Floppy etc.). With just the mobo and PSU, when pressed the power will remain on.

However, the moment I connect the CPU power supplies (from the PSU) to the board the aforementioned problem arises.

System stats are as follows:
Intel E6400 2.13GHz
Gigabyte DDR2 Mobo
9800 GTX GPU
4Gb DDR2 RAM
850w PSU

Thanks in advance for any help,

Christian

 

Re: PC starts up, then ~1 sec later shuts down. And repeats.Hi all, Have an issue w

Greetings, Christian...

First thing I'd try would be to reset the BIOS: if there's not a jumper for this purpose on the motherboard, then removing the CMOS battery for a minute or so should suffice...

A few other quickies: make sure the motherboard is not grounding to the case, reseat the processor socket, make sure the processor cooling fan is running, verify that any multiplier/timing DIP switches on the mobo are correct, reseat the RAM, etc...

 

Re: PC starts up, then ~1 sec later shuts down. And repeats.Hi all, Have an issue w

Is the fan on the CPU working? If not, the computer will shut down because the CPU would fry.

 

Re: PC starts up, then ~1 sec later shuts down. And repeats.Hi all, Have an issue w

Thanks guys.

Removed the CMOS battery - forgot and left it out for 4 hours whilst I went work rolleyes - didn't sort anything.

CPU fan works faithfully, as do all case and system fans. Removed heatsink and cpu, reapplied thermal paste and reseated. Removed the mobo and reinstalled it without tightening the screws so much.

Still the problem occurs when I apply the CPU power leads; if they are not connected to the mobo then it runs without the restart (although obviously does no form of boot).

If it helps, the PSU CPU lead is in two parts; two 4 pin connectors, green and yellow, marked CPU1 & CPU2. When I connect these up I can replicate the fault (unfortunately) over and over again.