posts and runs for a few minutes and then stops

Giagbyte GA-MA780G-UD3H
AMD athelon 64 x2 5000 +
4 gigs ( 2 chips) corsair
550 watt psu
Gigagybyte GTS 250 card
windows 7 ultimate

History: Assembled 2 years ago and finally worked well. Set aside for 1.5 year.

Tried to start now and will post and sometimes even load windows but system shut down after anywhere from 2 minutes to ten minutes.

Managed to read CPU temp via software and numbers seems to exceed specs. ( Only stayed on once long enough to see readings.)

Re applied heat transfer paste according to web info but had same problem with shutoff , even without external load ( mouse, keyboard & monitor). Same problem with graphic card out.

Problem: PSU ? CPU fan ? CPU ? or mother board ?

 

Does the system go through Windows Shutdown process or does it just stop as though the power plug was removed?

What OS?

Where was the machine stored for 1.5 years? Garage? Basement? High humidity can cause corrosion of some components. You may just need to remove, clean and reseat the removable components such as RAM, Video Card and Processor.

EDIT:
I was typing while MA posted.

 

Machine was stored in main room, dust blown out of psu and all replaced into a new frame so no humidity issue and everything cleaned.

Machine turns off suddenly like plug removed. No linux disk to start with. am loking for a new CPU fan although I vaguely recall testing the current system by exchanging it with another Ultra xwind that worked on my asus board. I purchased a hyper TX3 cpu fan which can't be made to fit despite their claims. I am looking for a fan to replace the ultra Xwind and get polar opposite reviews on most units.

 

More issues:
Gigabyte GA-MA780G-UD3h
Amd Athelon 64 x2
2 x 2 mb memory
550 W psu
1.5 tetabyte HD

Thanks for previous tips.

Finally got the beast to post but having repeated problems

loading windows 7 from bootable disk (Also tried with XP

x64 bootable DVD as well as Linux bootable DVD).

Formatted the hard drive on another machine after each

test.

When I try install windows itstarts to load window and

says

( windows will now reboot to continue). When it reboots it

starts all over analyzing my setup.

When I try installing in safe mode it turns off at the same

spot when loading files. When I try to install UBUNTO linux

it starts

to install linux and turns off.

After each setup I tried the fans will start but I have to

leave it off

appr. 10 minutes before it will and post after starting.

Someone suggested upgrading the Bios but I don't know

how to do that when I can only get to post screen without

windows loaded.

Question: is this a bios issue ?

I have removed the battery & shorted it (when power is

off).

Anything else I should test ? thanks