I have the 170, and am still in the honeymoon period (lol). Its a toss-up between double the cache or a higher multi. I don't believe multi's are as important for A64s, as the on-die mem controller allows you to run dividers and not incur a performance hit (like you would with P4s and XPs). I am currently running my 170 at 2.4GHz 1.40V, with a 166 memory divider. This keeps my mem at DDR400 speeds.