Something wrong with my computer?

1:When i turn my computer on there is a black screen with the words CPU scan failed!

Press F2 to reboot

Or computer will power down in 5 secs

Service your computer immediately!

Or something like that,i cant rmb it very clearly.

2:I have used AVG free antivirus and antispyware to scan my computer b4 but the scans showed nth.I have since deleted them bcoz they lag my computer up very badly.

3:My computer is now fast,but the screen i was talking about in point 1 is very disturbing.What is causing it?

4:I can turn on my computer after the computer powers down.

5:Everything seems quite ok after i turn on the computer.

6:There is no weird processes in windows task manager,but the CPU usage randomly jumps from high to low.Is that weird?

Can you pls help me?Im very worried and scared bcoz my sis's office stuff and my HW are all in the computer and we have nowhere else to store them.Pls help me!The computer is my life!!

Something wrong with my computer?systemworks

If you can boot into your PC I would suggest running any diagnostic tests that came pre-installed with your machine. Particularly system checks like your motherboard, and of course especially the CPU. You may have a hardware issue here. You can check to see if your CPU fan is not clogged with dust or otherwise not keeping it cool as it might be overheating. Sometimes it can be something that simple.