For the benefit of anyone who comes across this bug while searching, I gave up on nvclock for now, but I've found a workaround.
Of all things, nvidia-settings did the job. After adding the above "coolbits" option to my xorg.conf and rebooting, nvidia-settings gave me some new 2D and 3D (really performance levels 0 and 1) clock settings to tweak. So..I started playing with the 3D clocks (after turning the Overclock checkbox on). At first, the controls were useless - I would turn a setting down a bit, hit "apply", and the setting would revert to the default (325 MHz GPU and 700 MHz memory clock, in the case of my 6600). That is, until I got it in my mind to turn the GPU clock all the way down and applied it. Lo and behold, the setting stuck. I then proceeded to try other GPU clock settings (all of which worked), and eventually back to 325, and then turned the Memory clock down to 680 MHz -- bah! that didn't take -- it jumped back to 700 MHz. So I tried a little lower, and the same thing. After a few more tries, I found a spot somewhere in the mid 400's that caused it to jump to 502 MHz and stick there when I hit "apply". So I guess on this 6600, the GPU clock is pretty flexible, but the memory clock has only a few settings that it likes. So, the setting that works is 325 MHz for the GPU clock and a 502 MHz memory clock. I then set the "2D" clocks to the same values and they also stuck. Finally, to make the setting permanent, I created a new file: ~/.kde/Autostart/MySettings.sh ...and put these lines into it: #!/bin/bash nvidia-settings -l nvidia-settings -a GPUOverclockingState=1 -a GPU2DClockFreqs=62,700 -a GPU3DClockFreqs=81,700 nvidia-settings -a GPUOverclockingState=1 -a GPU2DClockFreqs=325,502 -a GPU3DClockFreqs=325,502 I then rebooted and sure enough, the clock settings stuck. nvidia- settings still shows the default powermizer clocks, but under the clock frequencies section, the values were as I set them. Of all programs, it was glxgears (maximized to one screen) with OpenGL sync-to-vblank turned off that made the artifacts appear the worst, so that was what I used to test with. The values returned are about 10% or so lower than normal, but I expected that with the slightly slower memory clock. The artifacts are now gone, thank G*d. Attached is an image showing what the glitches looked like before, in case anyone else needs to sort out the same issue. ** Attachment added: "graphic-glitch2.png" http://launchpadlibrarian.net/16207823/graphic-glitch2.png -- nvclock causes corrupt screen + hard lock https://bugs.launchpad.net/bugs/248600 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
