PC Reboots

[Hemi20]

Yesterday my Pc began to reboot itself quite a bit. So I started with the basics,
-tried another PSU
-disconnected everything and reconnected it
-clean for dust
-re-seated memory
-tried a different CPU/CPU Fan (both)

What it does is boot up login in to windows and sits for about 20 secs. Then shuts itself down. It seems to "click" when it turns off but im not sure if thats just the PSU or if its the CPU. Specs are-
HP d530c Desktop
2.66 gig intel
240 Watt PSU
1 gig ram ddr (4 256)
AtI Radeon 9800 XT
40 gig HD 7200
80 HD 7200
not sure what the Socket # is....or motherboard type.

Any help would be great!!! thanks!

 

[CCT]

The 'click' is more than likely made by your hard drive arm. Possible the hard drive is toast or is failing badly.

Can you put it into another comp and check it out?

 

[Hemi20]

Not likely since I started my PC up without the Hard drives connected at all and it still shuts down with the same amount of time.....Im getting to the point of thinking its the motherboard........

 

[wolfram]

A 240W PSU? That could be the cause.

 

[CCT]

"Not likely since I started my PC up without the Hard drives connected at all and it still shuts down with the same amount of time.....Im getting to the point of thinking its the motherboard........"

Well, since you are feeding data here as it suits you..........