[l008com]

OK, the 8500 came in four different speeds...
120, 132, 150, and 180. Each of those machines had the following bus speeds
40 , 44 , 50 , and 45 MHz.
That much I know, but the rest is confusing. Based on that, I was looking for an 8500/150 to use as a server. I was planning on eventually upgrading the processor to a slow G4. So I wanted an 8500/150 to start with because it has the fastest bus. But I just read that the but speed is controlled by they processor card. Does this mean if I drop a 150MHz processor card in an 8500/120, the bus will run at 50MHz? And does this mean that the bus will run at 50 MHz in any 8500 that I put an upgrade card in? It will make a big difference as 8500/120's go for much cheaper on ebay! :-D

[Taipan]

Yes, most if not all upgrade cards allow you to set bus speed via jumpers or DIP switches (and those that have a fixed bus speed wouldn't set it to less than 50 MHz, I guess). On most machines (especially some clones) you can even use up to 55 or sometimes almost 60 MHz, though Apple's machines usually are a bit more limited than clones in that respect. So yes, you might as well get a slower model if you want to upgrade, but you should also take into account that these might have less RAM and smaller drives (though I doubt you are going to use it in it's stock configuration). Especially RAM is worth some money.