Re: How to tell a bad CPU?
About the only way I know of is to install it in a mb with known good working components.
My first x2 4200 gave me all kinds of headaches with reboots and bsod's from the get go so I rma'd it and got a 4400 in place of it which worked flawlessly. I knew the components where in good working order as my 3700 was previously operating fine before installing and after removing the 4200.
Needless to say I chalked it up to a flaky processor, for some reason it just wouldn't run stable.
Have you tried making a boot floppy or boot cd with memtest86 to check the memory, is it a new mb?
i7 Beast: Asus P6T Deluxe, Intel i7 920 21x191 (4000) HT on 1.3875v, Swiftech GTZ/D5/BIX2
6GB (3x2GB) G.Skill pi Black DDR3 1600, ECS 9600GT
CM STACKER 810, PC Power & Cooling Silencer 750
i7 Game: Asus P6T, Intel i7 920 20x180 (3600) HT on 1.275v, TRU-120
6GB (3x2GB) G.Skill DDR3 1333 7-7-7-18, MSI GTX260 OCv2, Dell 3007WFP LCD
CM STACKER 830, PC Power & Cooling Silencer 750
AMD: Biostar 790GX A2+, PII X4 940BE 17x200, Freezer 64 Pro
4GB (4x1GB) Ballistix Tracer DDR2 800, Powercolor 4850