Quote Originally Posted by Cowering View Post
worker thread #1 is reported as a 'Pentium 4-type3' in the prime95 output window. worker thread #2 is reported as a 'Core2-type3'.
This is probably normal. On a Pentium 4, some FFT lengths are actually faster using FFTs optimized for the Core 2. Prime95 knows this and selects the right one accordingly. Admittedly, the "Core2 type 3" wording is poor/misleading.

I'll bet worker #1 and worker #2 are using different FFT lengths. If you can tell me which FFT lengths the two workers are using and if this is 32-bit or 64-bit prime95, then I can tell you if this is a bug or a feature.

I also own a Pentium D which I benchmarked to pick the fastest FFT implementation for each FFT length.