HT shows half it's speed


Jul 16, 2007
I have the AMD Phenom II X4 925 Deneb 2.8GHz 4 x 512KB L2 Cache 6MB L3 Cache Socket AM3 and ASUS M4A785TD-V EVO AM3.

My board only shows that I can take the HT up to 2000Mhz Max, but the processor specs show capable of 4000mhz.
I'm not too knowledgeable on AMDs, I admit, so I am curious as to why this is.
Is it a double data rate that applies?
As well, the motherboard bios allows me to change the HT to 16 -bit max, which i have.
As I said, not to familiar with AMDs as of late, but did some google search, still not satisfied with the search results, so here I am.