I gave a try to Hellae's guide and mods yesterday. I can verify that all worked out pretty well (thanks to the good silicon I got I guess). But something bothers me ...
They are 2x 64 + 56 - all at 1408/1100 with his mod's voltages (think 905).
1) GPU-Z is showing 1V on all 3.
2) The things are damn hot. The full other rig I have, using these settings (but modded at 1220 GPU and then set to 1407 with overdriventool) are running 47-55 with up to 2800rpm. The 3 fresh cards are at 62-65 with 3200 RPM ....
3) Power usage is around 670-690W on the 3 card system. I kinda expected a bit better , its nowhere near the advertized values it seems.
Any idea what am I doing wrong here? What can be done to fix the issue? One of the 64s was running alone with the oldcomer's mod with overdrive tweaks at under 50C for a week on top of my desktop ... Now where did that 15C temp increase came from?
I've had the same bug. Try to set P7 in overdriveNtool to 910mV (or 920, 930). This change lowered the voltage and the consumption for me.
This is very weird, I have not tried this with the overdriventool yet, but when setting the voltage at wattman at "manual" I suddenly started to get 50W less usage.
Sadly, after a restart - there was no way to reproduce this.
I am installing three more cards today/tomorrow, so I hope I manage to find a way to fix this. Especially the heat.
As I have no xp with 56er except this one - are they hotter than the 64s in general, or they should have same temps?