Ok, i think i understand what u meant now about differnt letters on the end...

Example... CUV4X vs CUV4X-E or CUV4X-D or CUV4X-DLS

CUV4X being the "base model". Just the standard board.

CUV4X-E is the same but with on-board audio & lan.

CUV4X-D is the same as the "base model" except it has a 2nd ZIFF Socket for a 2nd CPU so you can do a dual processor setup...

CUV4X-DLS is the same as above except it also has onboard audio & lan.

Any of them will work, and if u get ur hands on a dual CPU board, whats cool is you can use it with just 1 CPU and later on down the road if u want, u can buy another identical CPU liek u already have and throw it into the 2nd slot.

P.S. AMD > Intel.

Get an Athlon 64.

-Jay