hp pavilion a1440n power problems

I currently having problems with my HP Pavilion a1440n. It will randomly shut off with no warning and can't be restart for a few minutes. I first thought i might be the cpu overheating, so i removed the cover and place a fan in front of the cpu. After a half hour it still shut down without being prompted. Is this a power supply problem or is it a over heating issue?

If it is not a overheating issue then it must be virus problem. You can run "Recovery Program" to solve this issue. Usually, recovery program doesn't affact your files, however, for safety, store all your important files on CD or external USB storage device and then run recovery program. To run recovery program, restart your computer and keep pressing "F10" function key (for your computer version) and then just follow the guide to run Recovery Program (it will take couple of hours). Once everything is done, it will once again load the Norton Internet Security (60 days trial version) on your computer (as a part of Recovery). Scan your computer (Full Scan) to make sure computer is safe and working ok. Do not forget to scan files which you saved on external storage device (may be one or more files corrupted with virus). Make your computer virus free and enjoy.....