When I turn my PC on a get the page of specifications followed by the Windows page followed by a blue screen. Then the PC turns itself off and reboots again. And the same process repeats itself.

I have seen this happen when the RAM is bad or you have a virus. If it will boot from a disk then you have a virus and need to boot from disk, go to advanced section, delete partitions (C:), re-create C: drive, format, and re-install Windows. There is a virus that does this. DrTom4444

It all depends on what the error code displays. The problem is that it flashes by so fast you can't see it. In the past I have actually taken a picture as the blue screen appears then got the code from that; I would tehn research that error code and the fix. I would NOT start deleting partitions. Soemtimes it's a problem that can be fixed by booting to your Windows DVD and letting it do the repair. What OS do you have?

I found some info on this problem: Check the following-
http://www.computing.net/answers/security/virus-causes-automatic-reboot-loop/27279.html

http://support.microsoft.com/default.aspx?scid=kb;en-us;310396

http://techtips.salon.com/can-malware-cause-continuous-restarting-1223.html

http://www.computing.net/answers/windows-xp/reboot-loop-from-trojan-virus/55681.html which said:

"I just helped a customer with a virus displaying this symptom (reboot loop).
What causes the reboot every time win xp starts is a line added to win.ini
that invokes close.exe, which restarts windows. So, anyone infected with a
similar virus that causes "reboot loop" should check his win.ini file for
close.exe and delete the line containing that command."

I hope this helps. You did not tell us what operating system you had or the description of the computer. This would help us to diagnose it. DrTom4444

The PC turning itself off and restarting is a Windows feature believe it or not on XP on forward: Automatic Restart Vista - How To Disable the Automatic Restart on System Failure in Windows Vista

Often the issue is a corrupted Registry, which repairing from the Windows DVD can soemtimes fix.