Look dude, this is not funny anymore. You may fill up Suggestions with your name change requests and insults against us mods all you want but if I ever see you spamming your ZDTF/arcade forum babble in a legit marketplace thread again, I'll wipe your account in an instant. This is getting too far.
If I remember correctly there are 2 different clock speed A-boards that existed. I'm not sure if it can effect certain games or that certain games require that speed.
Edit:
Mercs runs on a 10Mhz 68000 along with SFII:WW.
SFII CE and "Hyper Fighting" run on a 12Mhz 68000 for example.