I have a radeon mobility 9000 and 4.3.0-2.1. The radeon driver doesn't seem to recover properly from screen blanking (there are several horizontal white bars with spurious activity around them). It recovers fine from a suspend however, so I find this strange. This is on a Dell Inspiron 8200, so after going to a console, and using Fn-D (blank screen) and waking it up a few times (almost always twice), the display recovers, and I can go back into X. I'm not using DRI if it makes a difference.
Created attachment 90588 [details] XF86Config file
Created attachment 90589 [details] xdpyinfo output
Please attach X log file from a problem run.
Created attachment 90595 [details] XFree86 log During the run represented in this log, there were several suspend/resume cycles which went fine and seem to be in the log, but I don't see anything from when the screen blanks due to a (hardware) timeout. I believe the blank is triggered from BIOS, not from dpms. In fact, I just tried 'xset dpms force off' and it was fine. Oddly, when I was running the vesa driver with 4.2.x in RH8, this problem didn't exist.
I tried a boot without apmd, acpi, or bios related blanking, and there were no problems. It really seems that this is a problem when recovering from a bios blanking since dpms blanking works fine, as does a recover from suspend.
Closing bug as NOTABUG, problem resolved as hardware having a buggy BIOS.