stupid question about ram on asus k7v

[mad hampster]

I got to thinking, and I am pretty sure one or two of the ram chips on my old LX board are pc100, I popped in two of them and it works so far with no probs and correctly shows memory. Does this mean they are pc100 or is there anyway to check? Also, I plugged the 3rd one in and the system hung when starting windows, is that a 66mhz ram chip?

Thanks