from 2-2-2-5 to 2.5-4-4-7 theres about a 40 mhz range, so if you plan to run htt300, then you have either choice, you can run your utt/bh-5 at 250 wiht 2-2-2-5 timings, or you can run tccd at 1:1 with 2.5-4-4-7, or if you want like 275 htt, slap on the 180 divider and run your bh-5/utt at ~250 with 2-2-2-5 timings or your tccd at 2.5-3-3-7. its up to you at what you want, they will both yield similar performance