(In reply to comment #14)
> I don't think that is correct. It can clearly be seen in Windows that Barts
> uses different idles for multi head than it does for single head, but uses
> the same mid and high. Cayman has a different system to barts too I suspect.

Windows has a very different implementation at the moment, but uses the tables
in a similar manor.

> Isn't that dangerous? It makes the card operate outside of the bios table
> profiles. You would, in some cases, be increasing the memory clock without
> increasing the voltage.

Good catch.  Fixed in v3 of the patch.