For info.

I suffered some really wierd issues over the weekend with the board.

First i flashed to 521 from the official site and all was well with my X6800 (indeed it did 4.5 without issue on freon). The i changed to my E6600 and could not find multi unlocking...

So i flashed to Beta 504 and sure enough the multi unlocking came up, but other parts of the bios were poor. so i flashed back to 521. On doing this the multi unlocked remained... good news i thought... No this is when the really wierd stuff happened.

At this point i could not get stable even at stock. In windows as i moved the mouse, or accessed HD the num lock keyboard loght would flash and ther would be a stuttering. This only happened when using Raid. After a few moments the system would just freeze.

I trued battery out etc - nothing worked. In the end i flashed back to 504. then flashed back to 521 - removing the battery between each flash. I also flashed in Windows XP using Winflash and did the old DFI trick of flash once and then without re booing flash again.

Anyway that got me back to stable, but no multi unlocked.... so for me 521 does not enable downward multi's which is a pain.