Multicore weirdness

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Fatwah on Western Digital
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I have a Server 2003 system where I just upgraded the CPU from a dual core Xeon 5000 to a quad core one.

Ordinarily, I'd be replacing the whole machine, but my customer can't really afford a whole system and I already had the CPU.

The machine has been using the ACPI multiprocessor HAL since the day I put it together, so it's not like I have to reinstall to see the new CPU, right?

Problem: It doesn't see the new cores. The BIOS recognizes and correctly identifies it. If I boot a mini-Windows XP install, it sees all the cores so I'm fairly certain the hardware is OK. But the existing Windows install doesn't see 'em. It sees two cores everyplace I can look and no more than that.

There's all kinds of people complaining that their Windows installs don't recognize new CPUs because they're running Windows Home or have the uniprocessor HAL, but I've never run into this before.

Is that weird or what?
 

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Fatwah on Western Digital
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Standard, 32 bit.

It's not a big deal. It's just not a behavior I've ever observed before. I figured Windows would auto-detect the proper number of CPUs and it doesn't.
 

sdbardwick

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Can often be fixed by run>msconfig>boot>advanced options>uncheck num procs (if checked) or selecting correct #procs>reboot.

Dunno why sometimes Windows doesn't pick up on additional cores.
IIRC, you can also update the ACPI HAL from device manager, but I don't remember doing that since Win2K.
 

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Fatwah on Western Digital
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Nope.

Adding /numproc=4 to my boot.ini (the GUI wouldn't let me) did not change the number of available CPUs after a reboot.
 

sdbardwick

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Crap. Haven't had one I couldn't fix via config for a loooong time. I have a vague recollection that messing with the HAL (going to uni then back to multi) fixed a box once upon a time...I remember being concerned with messing with the HAL b/c it can give all sorts of major problems (can't recall what version of Windows that was). It's too late for me to think clearly; maybe sleep will yield inspiration.
 

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Fatwah on Western Digital
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The first thing I did was try to reinstall the HAL. I've done that before.

I suppose I could do a repair install but that would involve me driving all the way back over there and thus is unlikely to happen, especially for something I wouldn't really be getting paid to do.

I also have some dim recollection that setting the numproc= switch to 0 is supposed to trigger a CPU redetection in Windows, but I tried that just now and that didn't work either.
 

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Fatwah on Western Digital
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That is what I don't want to do, since this work isn't really billable time and I'd have to actually go over there and do it.
 
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