Follow up on dual CPU weirdness - time issues

Daniel McNamara daniel at
Mon May 20 20:13:21 EST 2002

Sorry - correction that should be two PII 266MHz CPU's not 233MHz

Daniel McNamara wrote:
> Hey guys,
> Some time ago some of you may remember I sent an email to this list 
> regarding a weird situation with a dual CPU machine I have where the 
> system clock would run at double speed if I had an SMP kernel running 
> (didn't matter if it was the stock Red Hat SMP kernel or one compiled 
> from scratch) yet at normal speed if a I had a single CPU kernel running.
> After sometime of ignoring this machine whilst I got on with other 
> problems I've come back to it. A thought occured to me it might be a 
> hardware issue so I threw myself on Google and did a bit more looking. 
> What I found was a set of jumper settings to do with CPU core and bus 
> frequencies. The table which I refer to is found at:
> In the table labelled "JP1 settings". Having examined the CPU board it 
> would appear this board is currently set to 4/1
> However I must confess I have no idea what I'm looking at here in this 
> table. I brought this machine second hand and I have no idea if it was 
> in a different configuration prior to my purchase of it. It currently 
> has in it two PII 233MHz chips. Could anyone out there give me an idea 
> if I'm going along the right track here? Should the jumpers be on a 
> different settting? Or should not fiddle with them lest I nuke the CPU's?
> Anyone who could give me an idea of if this table is even relevant to 
> this situation would be helpful.
> Cheers
> Daniel

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