My old 9800p, flashed to xt bios:
412/365 (xt speeds), stock cooling = mad artifacts
445/375, vf700 = cool and fast
My current x800 is limited by lack of voltage on the oc, so it runs 440 core on both coolers but the temps are way better:
stock cooler, somewhat loud fan = 80C
vf700, much quieter = 57C