OS X.1 freezes for 5 of every 20 seconds


After a seemingly smooth install of OS X.1 and 9.2.1, when I reboot in OS X, I encounter a strange repeating system freeze.

I've timed it and OS X runs normally for about 15 seconds, then completely freezes for 5 seconds. Then it returns to normal, and the cycle then repeats - over and over and over... making it near impossible to get anything done.

Has anyone encountered this, or have any ideas why this would be happening?

I am running a G3/350 B&W, 128 MB RAM.
A couple more details I should have mentioned:
Under OS X, I shut down Classic Environment, but the freeze continued.
For peripherals, I have a 4x Que Firewire CD-R drive, A 4 port USB hub, and a Adaptec 2906 PCI->SCSI card, with a Zip drive attached.

I'm going to try shutting down all peripherals and pulling out the SCSI card next.
I have an iBook Dual USB DVD here and I am experiencing something similar to this system wide freeze.

about every 10 minutes or less my entire system becomes totally unresponsive a complete system freeze, and it doesnt get better unless I close the lid and put it to sleep, then it stays on for 2 minutes then it goes to sleep!! When I open the lid it works again, but then it happens all over again after a few minutes.

This is extremely anoying and the only thing thats keeping me from using 10.1 full time.

I should also mention that I have reinstalled and reinstalled with formats and everything twice already.... NASTY BUG!!!!

I've added a 40 GB Maxtor hard drive to my system, partioned it, and installed X 10.1. I also yanked my SCSI PCI card (I had to, as the 10.0 CD refused to boot otherwise.)

When I boot into this partition, the pauses are further apart.
Top and CPU Monitor show huge spikes of system usage, about 98%, every 30-40 seconds. The pauses last about 10 seconds. Unfortunately, I can never see a specific process that is hogging the system - the CPU usage flashes to 95%+, but nothing specific appears in the processes with that much usage.

RAM - top shows the following:
PhysMem: 19.4M wired, 71.2M active, 35.7M inactive, 126M used, 1.71M free
VM: 1.72G + 44.5M 15868(0) pageins, 11705(0) pageouts (this doubled after launching Classic)

The pauses continued, pretty much the same, even when free memory showed 15+MB.

I'm adding an additional 256 MB of RAM later in the week, will update again then...