Features

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Open Source Drivers

NOTE: The features listed are based off of the development repository at the time of this writing (2011-01-17). This does not mean that every Linux distribution will have the same capabilities. More than likely, major distributions will have an older, better-tested version of the graphics stack as a default and offer bleeding-edge versions of the driver in a repository. For a concise chart of features supported by the open source radeon drivers, see: http://www.x.org/wiki/RadeonFeature Here are the highlights:

* Kernel Mode-Setting (KMS)
* 2D Acceleration (EXA)
* DRI2
* OpenGL 2.x and GLSL 1.2
* Textured Video Acceleration (Xv)
* Power Management
* HDMI Audio
* XRandR 1.3
* AIGLX (desktop effects)

The developers also have a frequently updated list of 3D applications which they use to mark their progress: http://www.x.org/wiki/RadeonProgram

Switchable Graphic Chips Status

Some laptops (and other systems) are now being sold with both an integrated, low power GPU, and a discrete, high performance GPU AMD Switchable Graphics Technology Open source drivers support switching from integrated to discrete graphics cards using vga_switcheroo. However, the performance of the chips with the switchable open source drivers may not be optimized. For example, with the open source driver on the HP DV7-4045ea you can switch between the 4200 and 5650; the 4200 works okay, but although the 5650 does work, it does not perform well.

Video Decode Acceleration Status

While the video quality of the open source drivers is now in an excellent state as of kernel 2.6.38, we are still anticipating development of video acceleration code (using shader hardware).

ATI Catalyst/fglrx

ATI also offers a proprietary driver for RadeonHD chips based off of their Windows code (a legacy proprietary driver is offered for older cards, but it will not run on modern kernels/X servers)

* OpenGL 3.3/4.1 and GLSL(dependent on the latest version your card supports)
* XvBA video decode acceleration (through VA-API and only for RadeonHD 4x00 cards and later): http://www.splitted-desktop.com/~gbeauchesne/
* Direct2D acceleration
* Catalyst Control Center
* aticonfig CLI tool
* OverDrive (power management, overclocking)
* HDMI Audio
* XRandR 1.3
* AIGLX (desktop effects)

Video Acceleration (VA) API Status

Work has been underway to support VA API under in Linux. Video acceleration can be achieved through drivers supplied at gbeauchesne

However, the drivers do not appear to have been included in the mainline distributions and there is a certain degree of incompatibility. The distribution drivers and dependencies need to be removed and reinstalled with the older patched drivers.

For example vainfo on a clean Ubuntu 10.10 install for a 4200 shows the following:

* libva: libva version 0.31.0
* Xlib: extension "XFree86-DRI" missing on display ":0.0".
* libva: va_getDriverName() returns -1
* vaInitialize failed with error code -1 (unknown libva error),exit

The drivers in Ubuntu 10.10 are of a latter versions, but do not support VA API for ATI.

A bug against the libva has been submitted see Bug 642907

Switchable Graphic Chips Warning

WARNING

As of AMD Catalyst™ 10.12, there is no support for switchable graphics chips in Linux. This means you cannot switch between the low power consumption of the integrated graphics chip and the high performance of the discrete graphics chip. Some manufacturers allow the IGP to be turned off in the BIOS and use the discrete card only (but this is not good for battery life). Otherwise, you are stuck with both GPU's turned on and draining the battery while only being able to use the IGP. Carefully research before purchasing a laptop, or you may not be able to fully use the hardware you pay for.

There is a bug raised against the inability to switch between integrated and discrete graphics cards

EyeFinity

Catalyst supports more than two simultaneous outputs on RadeonHD5xxx cards having more than two physical independent out. Default settings starts every monitors in a cloned stage, but you can switch to a multiple display desktop via the Catalyst Control Center. Be aware that the ATI Catalyst Control Center does not let you fix arbitrary position settings : it only lets you approximately place your monitors on a virtual desktop. It's often best to adjust screen alignment using the "Position +x +y" option in xorg.conf.

EyeFinity support is still messy : As of 10.12, Five display setup on a HD5770 Eyefinity5 edition cannot be used. In any case, at least one display out shows a scrambled image (with a neat cursor and correct placement).