I gave my brother one of my Shuttle systems which I had been using with a 2.6GHz P4. He put a P4 2.4GHz in it which was previously in his older system. Both Socket 478, but I don't know what revision.

The Shuttle system (FS51 mobo) is "jumperless" and setting the CMOS to default-like settings appropriate for the hardware installed and/or completely clearing the CMOS will cause the system to boot and report it's running at 1.2GHz (100MHz x12) at startup. Windows (system properties) shows the CPU as "Pentium 4 2.4GHz" and right underneath reports it's running 1.2GHz.

In the manual and on an identical Shuttle system/mobo, in the Frequency portion of the BIOS there's some type of multiplier setting that can be changed to 12 or 24, etc... I've never touched any of that stuff with any CPU I've ever put into those systems. It's always just autodetected and worked. Anyway, on the system I gave him that setting seems to be missing. And the other settings, don't seem to allow for anything other than getting it to come up at about 1.6 or 1.8GHz (changing some number between 100, 133, 150 and some CPU:Memory ratio to 4:3, 1:1 or 4:5)

I've never seen this before and have no idea what the problem is. We were trying to wrestle with a completely different problem (corrupted registry) so I didn't take time to do CPU swaps or anything to try and isolate the issue.

Any ideas, suggestions, anything?

Bruno