<< Also, what is the fastest cpu you could put in this mobo? It is a ppga but are there fc-pga adapters? >>
I have the same BM6 motherboard...you can put in a cB0 stepped FC-PGA Celeron-II in the BM6 without modifications. I think the fastest cB0 chip Intel made was the Cel2-600. I have a FC-PGA Cel2-533 overclocked to 800 by changing the FSB to 100. This is probably the best route, though some put in 566s and overclock them to 850. Either way, you get that important 100MHz FSB.
Intel doesn't make cB0 stepped Celerons anymore, so it's something you'll have to find on the used market. In terms of using current chips, you should be able to use the $25 PowerLeap adaptor. I THINK you could technically install a P3-1000/100 in the BM6, but I'm not sure. I have zero problems with my CPU.