Appendix C. Supported graphics cards

Table of Contents

ATI Radeon series
Direct PCI memory access support
/dev/i2c-* devices support
/dev/i2c-* devices support
Direct PCI memory access support
i810/i815/i830/i845/i855/i865/i915/i945 with Integrated Graphics Controller
G200/G400/G450/G550 series

/dev/i2c-* versus PCI memory

To control a monitor, DDCcontrol must access to the I2C bus of the graphics card. There are two methods to do so: the first one uses /dev/i2c-* devices provided by kernel drivers (abbreviated by dev in tables), the second one reads and writes directly in the card PCI memory (abbreviated by PCI in the tables).

Depending on your hardware, one method or the other works, or even both.

ATI Radeon series

Direct PCI memory access support

Almost every ATI cards should work with direct PCI memory access, even if it has not been very extensively tested.

To use it, you have nothing special to do, everything is done by DDCcontrol.

/dev/i2c-* devices support

ATI Radeon cards also work with /dev/i2c-* devices. To use /dev/i2c-* devices with ATI cards, you must load the radeonfb module by typing, as root:

# modprobe radeonfb

The kernel configuration options needed to enable Radeon framebuffer driver and I2C support are:

  • Devices driversGraphics supportFramebuffer supportATI Radeon display support.
  • Devices driversGraphics supportFramebuffer supportATI Radeon display supportDDC/I2C for ATI Radeon support.


    The radeonfb kernel module may cause system instability (crashes or screen corruption) when used at the same time as used the ATI closed source drivers.

    This is why we recommend that you use direct PCI memory access with ATI cards.

ATI cards support table

These ATI cards have been reported to work, but others models should also work. If yours is not listed, please send a message to one of the DDCcontrol mailing lists (see Appendix A, Report problems and successes).

Name Works
dev PCI
Radeon 7000 Yes ???
Radeon 7500 Yes ???
Radeon 9200 Yes Yes
Radeon 9200 SE ??? Yes
Radeon 9500 Yes ???
Radeon 9550 SE Yes ???
Radeon 9600 Pro Yes ???
Radeon 9700 Yes ???
Radeon 9800 Pro Yes Yes Logo