what is most thorough x86 CPU testing program?

A program to resize JPEG pictures started failing with
"floating point error"
When I swapped the Celeron from another PC, the error
went away. Put the original CPU back, the error returns.
But when I tested this sick CPU with a couple
of "diagnostic" utilities, they found no fault.
So I enquire what CPU testing software is best in the
sense of most thorough testing? I realise complete
testing is not feasible, e.g. 2+4=4 works but
2048+2048=4096 fails. Plus all the extras, 3Dnow/SSE etc.
Any suggestions for an x86 CPUtester?
(MS-DOS or Windows program)

In article <1191803863.065641.132990.DeleteThis@50g2000hsm.googlegroups.com>,
u235bomb.DeleteThis@ml1.net says...
> A program to resize JPEG pictures started failing with
> "floating point error"
> When I swapped the Celeron from another PC, the error
> went away. Put the original CPU back, the error returns.
> But when I tested this sick CPU with a couple
> of "diagnostic" utilities, they found no fault.
> So I enquire what CPU testing software is best in the
> sense of most thorough testing? I realise complete
> testing is not feasible, e.g. 2+4=4 works but
> 2048+2048=4096 fails. Plus all the extras, 3Dnow/SSE etc.
> Any suggestions for an x86 CPUtester?
> (MS-DOS or Windows program)
>
Sure. A program that resizes JPEGs.

--
Keith