RT-compatible video card

[khz]

I would be interested to know which graphics card, with non-free driver and RT kernel, you use.

GMaq uses the AMD Radeon RX 570 successfully.

Do I read this correctly?

3rd Party Video drivers by nVidia and AMD are not supported to build with RT Kernels..

For example I only find graphics cards with "graphics chip :: AMD NVIDIA".

My question to everybody: What ~cheap, good graphics card can you recommend to me to enjoy RT AVLinux?

There seems to be only AMD and NVIDIA graphics chip. Or am I missing something or misunderstanding something? I'm a bit at a loss.

[GoaSkin]

The market is dominated by graphic cards with NVidia and AMD chipsets. Almost all manufacturers of graphic cards use the chipsets by them. The only other one I know is Matrox.

But regarding NVidia and AMD, there are 3rd party drivers as well as community-driven Open Source drivers. While the original NVidia driver may not be supported, you could try out the Nouveau driver. It is not so comfortable like the 3rd party driver but it may be sufficient for that what you want to do.

[murray]

I would be interested to know which graphics card, with non-free driver and RT kernel, you use.

GMaq uses the AMD Radeon RX 570 successfully.

My question to everybody: What ~cheap, good graphics card can you recommend to me to enjoy RT AVLinux?

As was said, Nvidia and AMD are the only real distributors of the graphics cards/chips you're thinking of.

How realtime are we talking? Do you really need a real-time kernel? There's quite a bit of latency inherent in graphics cards due to the hardware data transfers (PCIe), so I'm a little suspicious of your use case.

I use 'low latency preemptive desktop' kernel option on my Gentoo Linux systems that I use to sync my audio to GLSL shaders rendering "realtime" on my GPU--either a desktop with nvidia RTX 2080ti or a laptop with nvidia gtx 1050ti.

[GoaSkin]

Like I said: For both chip manufacturers: NVidia and AMD there exist Closed-Source 3RD party drivers as well as open source drivers. The open source drivers also support hardware-accelerating technologies like openGL or VDPAU, multiscreen-setups and so on but are less comfortable to configure. As long as the computer isn't used for very complex video setups and for gaming, the open source drivers may be sufficient and can be used with the Realtime Kernel.

And the third chipset manufacturer is Matrox. But the Matrox cards are very rare and if you have difficulties to set them up, you may find nobody who can help you. Their focus are multi-head graphic cards to set up videowalls.

[khz]

A GeForce GTX 650 with the free Nouveau drivers works reliably.

[Jack Winter]

I can only contribute that the NVIDIA driver is kind of crappy as it increases the kernel scheduling latency (as tested with cyclictest, a test program contained in rt-tests). In normal use the scheduling latency is higher than say the Intel driver, but not too bad. But it spikes pretty badly at some operations, like starting video playback, etc.

One can only hope that this will improve when the full rt configuration option makes it into the vanilla kernel.

[khz]

One can only hope that this will improve when the full rt configuration option makes it into the vanilla kernel.

Totally agree!

I find it ~sad that you can "only" use the non-free driver with a RT kernel. This driver does not support 100% of all functions of the purchased graphics card.
That could be because some companies don't give a damn about us Linux users, no free documentation and/or cooperation with the kernel developers.
That soon the official kernel is 100% RT capable lets us hope, or not = hardware is no longer usable.

[Jack Winter]

Well you can use the NVIDIA driver with a rt kernel, but AFAIK you have to patch it as by default it refuses to install on rt. I suppose we are a very small minority using a rt kernel, so it's not a priority. It used to work without patching, and then when it started hanging the system on a kernel change, they just disabled the driver building instead of fixing the problem. Once the problem was fixed (don't know if it was in the kernel or NVIDIA driver), it's stayed disabled???

On Archlinux it's relatively easy, just install nvidia-dkms, and it will be automatically built also for the rt kernel.