SCSI controllers 32bit and 64bit

just out of curiousity. you can use 64bit PCI controllers in regualr PCI slots right. 64bit controller cards just have more channels. isn't that how it works?

No. The 64 bit PCI slots are about twice the size of a regular 32 bit PCI slot physically. They also run on 66 mhz as opposed to 33 mhz. You'll need a 32 bit controller if you wanna use it in a 32 bit PCI slot.

64-bit cards are no different than a 32-bit card physically (other than an extra notch in the 64-bit cards)...they also don't necessarily need to run at 66MHz. There are plenty more 33/64 cards out there than there are 66/64 ones.

Only thing you need to look for is 32-bit backwards compatibility listed in its description so that you know it works in a standard 2.1 PCI slot and can work at either 3.3V or 5V.