2x 1ghz CPU's Stuck On 366 Mhz (NetServer E800)

[L8on]

'lo,
It's getting late and I'm losing my mind.

I have a NetServer E800 with two 1ghz CPU's. Both CPU's are recognized by the BIOS which is running version 4.06.18 PQ, however neither clock at 1ghz but are stuck firmly at 366Mhz. The machine boots fine, just 'slow'.

Originally a single CPU machine, it had quite happily chugged along at 1ghz for as long as I've owned the machine - until this evening.

I then removed it, annual dust of the heatsink and replaced. While I had the case off, I added another identically stepped 1ghz chip and -poof- both chips now clocking at 366Mhz. Both chips are branded Intel, both are identical in speed, FSB, voltage and stepping.

It no longer matters if I have either CPU in either slot, neither will clock back to 1ghz even when install singularly. So, even if I put the original 'used to work just fine' chip back in, on it's own with the dummy die in place, I still only get a single CPU 366mhz machine. Joyous.

Please help - I'm pulling my hair out! I updated the BIOS but that didn't help.