czebrda,
Are the cards in use when you adjust the clocks? In other words -- try starting the miners first and then adjusting the clocks. See what happens... ATI has a power saving feature in their drivers that disables video cards that aren't in use (basically, the cards are in standby). While they are in this mode, the clock rate cannot be changed. On my windows box with 3x 6970's, I can't adjust the clock rate of my 3rd card unless it's already mining (or unless you disable the power saving feature altogether with a registry hack. Can't remember the ATI acronym though. Starts with an O. If it turns out to be your problem, I'll hunt down the registry hack again.
Which of the cards (if any) are crossfired?
Yes, I am aware of this issue and it is true that these cards have three clock settings in their BIOS - one for idle, one for normal (e.g. windows desktop) and one for high performance (e.g. playing games or mining). So the mining has always been in progress when I tried these tweak apps, even though for some reason on the screenshot it shows Load: 0% for all cards. When I run clocktweak -r it shows the load correctly though.
The thing is, that ATI Tray Tools can give me 960/300 on the first two cards for all these regimes (idle/norm/HP), so the clocks stay there all the time no matter if u're mining or not. That's why I wonder why no other app can do the same.
None of the cards is crossfired, I use VGA dummy plugs.
