PC problem - unknown

[lostindos55]

Hello All,

I was wondering if anyone can help.

I have a PC that will not power on at all.
I need to narrow down what is wrong with it to replace whatevers needed, but I don't have any spare PC bits to test it with, I was wondering if anyone has any ideas how I could narrow this down.

The PC is a core 2 duo, when the PC has all power connected to the motherboard, it will not start up (no fans etc) however, once the CPU power cable is removed, and the motherboard cable left in, all the pc parts, fan etc start to work.

but whenever the CPU cable is in it will not start.

Its got to either be the CPU, mobo or PSU I guess, based on the above i'm guessing it could be the CPU?. anyone have any ideas, or know if the above sounds like a CPU problem?. Thank you

 

[Helloworld_98]

are you plugging an 8 pin or 4 pin CPU cable in?

 

[lostindos55]

its a 4 pin CPU cable. power comes on when its not plugged in, but wont post when its in. this was sent to me a a faulty PC, suspected PSU problem, but since the power comes on when the CPU power is not connected I was wondering if that could be a sign of anything else.

Anyway I can narrow this down?. Thanks

 

[dhicks2008]

Hi there, sorry to hear bout you problem , pcs are wonderful like that. I probably would think its the motherboard or the PSU. The only way to test it really is to try another PSU on the system. If thats the same then its more than likely the motherboard is faulty

 

[lostindos55]

Hi, Thanks.

Yeah its for a friend, but I guess the only way is to try other bits.

I have a multimeter, is there any way I could rule out the cpu,motherboard or PSU?.

the PSU powers the computer fine when theres no CPU 4 pin connector attached. so for some reason its shutting off when the CPU power is connected which made me think it might be the CPU rather than PSU?. Thanks