cache says 256

I have an asus p4b mobo with 512kb level 2 cache but my bios boot screen says cache 256k when i disable L2 cache in bios it goes to 0 even with L1 cache still enabled and if i enable l2 and disable L1 it goes back to 256k shouldnt this be saying 512 at least the size of L2 cache and what about L1???

What cpu do you have? The mobo doesn't have any cache - only the cpu. If you have a willy core then 256K is correct.