Great... Thanks for the site.. So, I assume that I'd be ok with a p3 if I'm only going to be capturing 1 or 2 cameras at a time 120fPs total with no audio? I'm mainly going to be using the cameras for live viewing..
(below cut from website)
GV650, 750, 800, 900, 1000 models have 2,3,4,8,16 Bt878 "A/D capture" chip sets respectively. The factory uses a "HINT" chip to balance load and to control PCI bus traffic from these multiple Bt878s. This HINT chip conflicts with motherboard having VIA chip set; therefore, do not use motherboards with VIA chips. Also, use AGP video cards that supports Direct-X version 9. You can freely use any CPUs such as Pentium, AMD, Celeron etc.
If you capture up to 120fps at 320x240 pixel size with 4 channels of audio, all you need would be a P3 800Mhz. However, if you capture at 640x480, you need 4 times the CPU power. (Cannot capture audio with this video setting.)