Intel 478 v 478B CPU

Is there any difference between the Intel 478 and 478B CPU's or is just nomenclature? I have a 478B cpu and the motherboard specifies 478.

Thanks

It doesn't depend on the socket, it depends on the chip. There's only one Socket-478 & the different CPUs available for it are the folowing P4 : 100 mhz FSB / 256kb of L2 cache P4B : 100/133 mhz FSB / 512kb of L2 cache P4C : 200mhz FSB / 512kb of L2 cache P4E : 200mhz FSB / 1024kb of L2 cache