Setting gamma and brightness
Intel offers no way to adjust these at the driver level. Luckily these can be set with
Adding acpi_backlight=vendor to the kernel boot line allows the backlight to be changed on the Intel HD 3000 via xbacklight without root access. Perhaps a note could be added to provide this option.
papabean (talk) 02:40, 14 January 2013 (UTC)
acpi_backlight=vendor stopped working a few kernels ago. (No. I did not revert to be certain).
Best performance options
In my experience (i5 CPU w/ HD4000, Z77 mobo) the best performance can be had with the following options:
- SNA acceleration method
- Vertical sync enabled
- TearFree option enabled
i915.semaphores=1kernel option turned on
Using the ck kernel specific to the CPU architecture also seems to make the video performance more consistent, but not necessarily any faster.
I suggest that the restoration of this entry, it was very useful
To disable VSYNC, adjust
Section "Device" the string
Option "SwapbuffersWait" "false".
~/.drirc and make sure that
driver is set to
<device screen="0" driver="dri2"> <application name="Default"> <option name="vblank_mode" value="0"/> </application> </device>
Is there a way to do the equivalent of
xrandr --output HDMI3 --set "Broadcast RGB" "Full" without having X running? I have two identical monitors (Asus VH222H), one connected to my dvi port (HDMI1), the other to the hdmi port (HDMI3). Both support full range rgb, but the one connected to hdmi always boots set to limited range. Its easily fixed with the xrandr set command, but I don't like running that all the time and it also doesn't work if I go straight to a vt after booting. It would be nice to put it in a systemd job.
Perhaps I should file a bug report with the kernel? The auto detect is more sophisticated than just HDMI == limited range tv, right?
Corrupted fonts after resume from ram
I've finally found searching across many forums the solution for my i915 graphic card.
My card is: "Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller (rev 04)".
The problem is: After resuming from ram, some letter have a missing orizzontal line, for example I see ¦ instead of |. Another thing is that sometime, after resuming, the cpu goes to 100% of usage with no apparent reason.
The solution is: Create the file /etc/modprobe.d/local.conf (if it doesn't already exist) and add to it the line "options drm_kms_helper poll=N".
I cannot understand this mystery but now I can use "Suspend to ram" as many times as I want.