When using the radeon driver (I have an ATI 800XT PCIE card) it seems to be unable to use the DPMS mode. When I do a 'xset dpms force off' it just blanks the screen, and doesn't really turn it off. I get the same effect by just allowing the appropriate time out to occur (i.e. I don't think it is really associated with forcing the mode via xset). I also tried the vesa driver, but it can't even blank the screen.
Created attachment 4203 [details] Copy of my Xorg.0.log file. A copy of my Xorg.0.log file.
Hmm. Seems you have to put 'Option "DPMS"' in the monitor section to enable DPMS even though it was clear that the monitor was DPMS capable via the log file (i.e. I thought it was enabled when it menitioned that the monitor was DPMS capable).
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