I start my system, It works fine for a period of up to 15min-30min then suddenly it gets gets struk.Sometimes it just turns off abruptly.sometimes it gets struk or shutsdown while booting itself.

I opened the system case to see whether the processor fan is working,and it is rotating even if it has turn off abruptly.It turns off when i switch off the cpu.

It is not a operating system problem because it is happening the same with linux also.

i Have a celeron 700Mhz processor,mercury KOB810FCST motherboard and i bought the system 41/2 years ago and this is the first time i am facing this problem.

somebody out there please get me out of this problem.This is annoying me a lot.

- Siva kumar reddy.CH.V

Clean out all the dust bunnies, canned air is fine (don't shake). A power supply that is dying is also likely.

Make sure all connections are secure, reseat all cards and RAM modules making sure they're fully seated, check that all fans are running(incl. the power supply fans), make sure all vents are unobstructed, and there is no dust built up inside the case and on the fans and heatsinks(You may have to remove the CPU and video card fans in order to clean their heatsinks).

If those are ok, then check the MB capacitors for signs of leaking, bulging, or rupturing. If any of them show these signs, then replace the MB.

If no luck, then remove the computer's cover, and run an external fan.
If this works, then check the CPU and system temps in BIOS.
If the CPU temp exceeds 60 C, then replace the thermal compound between the CPU die and the heatsink(Arctic Silver is recommended).
If the system temp exceeds 40 C, then consider installing additional or more powerful case fans(Lower front blowing in, and upper rear blowing out are recommended).

If the system is not overheating, then swap out the video card.

If no luck and multiple RAM modules are installed, then install one at a time.
If the problem happens with a specific module installed, then it's bad.

If no good, then check the power supply voltages:
http://www.ochardware.com/articles/psuvolt/psuvolt2.html
If you do not have a voltmeter, then swap out the PS.

If no luck, then the MB may be bad.

thnx a lot for the guidence. i will look at the temparatures and will reply back soon.