This board (Ultra-D) is a real challenge - went from a lowly Asus A8N-E (v-core/chipset volt modded) that would run my opty 144 at 2.94 (327htt) with 2 x 512mb OCZ Plat Rev.2 at 1:1/2.85v/2T(A8N series mobos don't run 1T above 240-250).
Grabbed an Ultra-D refurbed (I realize that could be my problem) from Newegg and flashed it to 704-2BTA - and initially was able to run it at 311htt, ram at 1:1/2.9v/1T - nice and fast. I tried 623-3 bios to see if I could get up to 322htt, but it wouldn't let me past 266, so back to 704-2BTA (after a nice long cmos clear and battery removal) which resulted in all sorts of craziness - can't run past 277htt, even getting memtest errors in windows at default speeds. if i lower the multiplier from 9x to 4x, then the board will go up to 370htt depending on the ram ratio. Also I need to feed my OCZ TCCD 3.0v now to get stabilty at 1:1 at anything above 266htt. I have spent too many hours playing with timings, bios revs, voltages, swapping dimm slots, etc. and this thing is making me crazy. The board sits in an open case in a very cool garage and is water cooled, and my TCCD sticks have active cooling on em.
Not sure what I am asking since I've been o'cing stuff since my Pentium 60 and and have recently run 3 different NF4 boards (2x A8N-Es and a crappy Gigabyte) and a variety of Venice cores, a San Diego and now an Opty, and have spent much time on these forums. Just seems like I rolled the dice on a refurb and lost.