Originally Posted by engineerof2005
what about asrock z77 extreme4/extreme6 (with vt-d support) compared to asus p8z77-v (not sure about vt-d support)?
K processors don't support VT-d, only the non K versions support it.
I'll ask again: what CAD programs are you using?
Going for faster CPU's and better motherboards won't be anywhere near as important as the GPU if the program can use it.