video card replacement - hdmi

Although it looks imposing and is potentially a solid choice, I became tired (2019) of the 2Gb nVidia GeForce GTX770 (GK104 Audio Controller onboard) that came with my system.

Maybe it's an nVidia thing, but it had the nasty habit of ramping-up sound instead of turning audio on immediately. This meant that, after any silence, sound always returned smoothly, however it made video editing impossible. Sound needs to match video precisely and, since we're not going to play back video on only this nVidia system, we need to know volumes exactly, not with system-specific audio ramping.

nVidia vs Radeon

According to the proprietary utility nvidia-settings (in the nVidia driver), my motherboard has a PCIe Gen3(16bit) slot. I'm not a gamer, but for Blender's sake, I doubled GPU RAM with a 4Gb Polaris based AMD Radeon RX560D.

Again, however, the main factor is having audio that works correctly. There was simply nothing I could do to stop the nVidia card audio ramping. All automuting, all of that was disabled, but the nVidia sound always ramped instead of immediate.

Remove nVidia software

Once replaced, i uninstalled the nVidia module in favor of amdgpu module.It's just sitting there and not being used so it doesn't really hurt anything, but it's a 200Mb of orphaned stuff. I ran # pacman -Ss nvidia to see what I had installed and removed all of them...

# pacman -Rdd libvdpau libxnvctrl nvidia nvidia-utils

audio

When I had the nVidia card, I was never able to pass the dreaded same-named sound card issue...

$ cat /proc/asound/modules
0 snd_hda_intel
1 snd_hda_intel

...which would sometimes provide sound and sometimes static.

libva v libvdpau

I still don't understand if I'm supposed to have both the Intel and the nVidia video hardware acceleration. I knew that va was intel and vdpau nVidia, so which/what to use on with the amdgpu and a Radeon. At some point, because Chromium appeared to favor vdpau, I installed vdpau, and did so by installing its utility, vdpauinfo...

# pacman -S vdpauinfo

... which also brought in libvdpau. Following this, Chromium opened normally, and YouTube functioned.

xorg

With the nVidia software removed and the amdgpu package installed, X refused to initialize. The error and the solution discussion are here. The solution required a change to /etc/mkinitcpio.conf...

MODULES=(amdgpu)

... and then

# mkinitcpio -p linux

After this, X loaded normally.