I think we need a few more details on what 'bank' and 'slots' means to you.
Slot (somewhat obviously) is a memory slot on a mobo, correct?
Bank?
Do you mean a 'bank' as defined by a mobo? In that case, it depends on the mobo - some are 1, some are 2, some are 4, etc.
If not, I guess I need a reply to clarify...
Mike.