Computer starts for 5-10 sec then restarts.

viion · 6 Jan 2010 at 09:39

My computer will start up then after 5 seconds turn off, then restarts or retrys. There is no boot screen or anything, just the lights and the machine running.

All the components are in correctly, i've thoroughly checked it.

It was working fine yesterday but now it wont.

I've tested individual ram, but all ram works fine in another machine
Tested PSU on another machine, was fine
GPU tested on another machine, was fine

I've had a similar problem like this before where i had to replace the cpu with an old one, just to flash the bios, and it worked. I cannot do that now because I do not have another cpu. I dont know why it would even do this now as the bios should have fixed this, it did for a year.

Any suggestions? my only guess is my mobo is naffed, I've had problems with it over and over for past year: Randomly loses connection to graphics card, randomly doesnt boot pc on normal mode (only in safemode).

Specs:
AMD Phenom II X4 Quad Core 965
Gainward GeForce 9800
Asus M3N-HT Deluxe HDMI nForce 780a
Coolermaster Real Power 700w

J.B · 6 Jan 2010 at 09:51

Try clearing the CMOS

One stick of RAM

Disconnecting the power button and shorting the pins out to turn it on

Building it outside the case to check if something is shorting out.

viion · 6 Jan 2010 at 09:54

I had it out the case yesterday as I just moved house and I took my pc parts on its own as the case is very heavy to travel with, for few days it was fine out the case, been fine in case for a year, now it wont work outside or inside case, I tried everything you mentioned, no luck, Even now It wont even boot, weather I use case or circuit it has no reponse, the green light is on the motherboard so there is power to it. also ethernet lights

rodo · 6 Jan 2010 at 10:49

I had green lights on a motherboard once but it was till dead

viion · 6 Jan 2010 at 11:41

I bought a new motherboard, not fun, had to walk and snow is like a foot deep! lol

Anyway My guess is the old motherboard was faulty, i mean the constant issues of it, even the ethernet socket stopped responding one time and i couldnt get internet for a whole day, after constant reboots it started to work again.

Hopefully the new one will drown my sorrows of the old one lol gunna try it now.

I got through to technical support (not system support) of OCUK and he said it would most likely be motherboard.