If by crash you mean the PC "hard locks", then this is a known problem, and has been discussed extensively here.
 
You can:
Roll back to pre 3.66 drivers
Disable AGP using DXDIAG
Remove a CPU.
 
 
------------------
SuperMicro P6DBS (dual UW-SCSI) BIOS 2.2, 2*Celery 300a @ 450Mhz, 384MB PC100 RAM
SCSI-A=4.3Gb+9Gb, SCSI-B=Tosh32x CD-ROM, Yamaha4416 CD-RW, Iomega ZIP100, IDE1=4.3Gb
IBM EtherJet 10/100 NIC PCI + Nortel ADSL "modem"
Matrox G400 DH 32Mb AGP + Quantum3D Voodoo2 SLI PCI (CL TNT1 AGP on a shelf)
SoundBlaster Live PCI (not Value)
Win2K build 2195 Retail (not 120-day eval)
 
[This message has been edited by YuppieScum (edited 01 March 2000).]

I have tried the 3.66 Nvidia drivers and disabled agp, neither of which helped. Removing a cpu would defeat the purpose of running smp I have no issues with the game when smp is turned off. Any other suggestions?

I have the same ptoblem on my PIII500
 
I have tried everything but nothing seems to help.....

I haven't had any problems with Q3 not working (don't use it in SMP mode), but other GL apps like 3D studio hard freeze with multiple CPUs with nvidia drivers.
 
For the time being, go into device manager and change "Computer to Uniprocessor MPS system" until nvidia has fixed the driver problems. If you are using dual celerons, you will probably notice a bit of a speed increase because the limited l2 cache is no longer playing handshake with the 2nd CPU.

You can also change the affinity of the program by opening the task manager/processes and right clicking (I believe) on the process/program. You should have choice of set affinity -- set it to one of your two (or more) CPUs so that the process only runs on one. I know this worked in NT for my problems with Hereos Of Might and Magic 3 on a SMP. It will allow you to keep the CPU in and have Win2K in SMP mode without loosing anything (speed or otherwise) except in the game itself.

You're using a BP6 aren't you. I had the same problem. The best way I've found of geting it to work with a geforce is to switch the AGP from 2/3 to 1/1, I've never had a Q3 crash since even after playing Internet games for 5-6 hours.
Another way that worked on another system of mine was to upgrade the power supply from a crappy 200w to 300w and make sure to 3.3v line is capable of supplying a lot of current if needs be.

Running the 3.66 drivers meerly cripples some of the features of the geforce this can be seen in benchmarking programs. This means that the chip is using less power and this may also be the reason that the geforce becomes more stable

Try this I cant promise it will work for you but it did for me now the games burnin. Do a full install then head on over to www.gamecopyworld.com (patch only to be used for your own use if you own the cd!!!) and pick up the no cd patch "Quake 3 Arena Point Release Jan1300 No-CD" on the Quake III previous patches page. Run the point release patch then backup the Quake III.exe from program files then add the new no cd patch run the game it might "hard lock" the first time or two but after that its fine. Then as soon as you get to the main menu set up your all your options and before you run the game drop down the console and type /r_smp 1/vid_restart to enable smp and hit enter it will tell you smp will be enabled on restart. Exit to the desktop and then reopen once I played the first level it never locked up again !!!! Good luck
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Windows 2000 final 2195
Supermicro P6DGE
Diamond TNT2 Ultra / Nvidia 3.78 Drivers
Dual Pentium PIII 550`S
256mb ram
Soundblasterlive
 
[This message has been edited by badboy (edited 09 March 2000).]
 
[This message has been edited by badboy (edited 09 March 2000).]