Mine is rock stable at 8x400 with my E6420 at stock vcore, 1.75 Vmch and 2x1GB Ballistix 5300 @ 5:4, 4-4-4-12 (left RAM slack to test the CPU/NB) however even 1 or 2 MHz over the 400 FSB and it fails Orthos/OCCT in mins or seconds.

This is with 13 beta and 15 offical BIOS, using 1333 strap. I v-modded for Vmch drop and watercooled the NB but no improvement at all. There is a wall somewhere on this board, but I still love it