You may be able to get CPU temps from the BIOS. So you could check this without opening the case.
I somewhat agree that a cracked CPU generally is a it works or doesn't. But in servicing computers, I've seen where broken solder joints don't manifest themselves until the reach certain temps. At that temp, the circuit is open. When it cools back down, contact is restored until it heats up again.
FWIW,
TB
Tony Boner
Personal: 98cdw27@charter.net Work: tony.boner@sun.com
Saving the computer world from WinBloze as Unix/Solaris/Java Guru
http://www.sun.com 1998 Contour SVT Pre-E1 618/6535 Born On Date: 4/30/1997
Now with Aussie Bar induced mild oversteer.