Exploring current options for freedom-friendly desktop graphics cards

I'm currently in search of acquiring a graphics card that operates without blobs, and I want to explore the possibilities available.

To begin with, I'm aware of the existence of Intel integrated graphics cards (such as Intel UHD) that would work well for a laptop, but I'm looking for a graphics card for a desktop computer.

So far, I've been using AMD, but they require blobs, and I want to be able to use Trisquel and Guix without any issues with Linux-libre.

I would like to know which ones are the most powerful that do not compromise my freedom (except unfortunately for the GPU BIOS, which I know as of today there are no free GPU BIOS available...).

From highest to lowest power, based on NVIDIA, we would have, all from the Kepler family [1]:

1. NVIDIA GeForce GTX TITAN Z [2] (seems to be equivalent to 2 Titan Black)
2. NVIDIA GeForce GTX TITAN BLACK [3] (this one doesn't appear in the list [1] for some reason, but "I believe" it would be compatible with Nouveau since it's from the Kepler family; it would be good if someone could confirm this).
3. NVIDIA GeForce GTX 780 Ti [4]
4. NVIDIA GeForce GTX 780 6 GB [5]
5. NVIDIA GeForce GTX 780 [6]

This list could be useful as it is indexed by search engines for those users interested in software freedom who want to see how far they can go in graphics power.

My goal would be to create a list to later choose according to availability, prices, among other factors, for an ASUS KGPE-D16 motherboard with GNU Boot and, in the future, for an openPOWER motherboard such as the Talos II.

On the other hand, Red Hat has announced the Nova driver [7], which aims to be a replacement for Nouveau on modern GPUs, but it is most likely to require blobs to function, so for now, we are still in the same situation.

[1] https://nouveau.freedesktop.org/CodeNames.html#nve0familykepler
[2] https://www.techpowerup.com/gpu-specs/geforce-gtx-titan-z.c2575
[3] https://www.techpowerup.com/gpu-specs/geforce-gtx-titan-black.c2549
[4] https://www.techpowerup.com/gpu-specs/geforce-gtx-780-ti.c2512
[5] https://www.techpowerup.com/gpu-specs/geforce-gtx-780-6-gb.c2707
[6] https://www.techpowerup.com/gpu-specs/geforce-gtx-780.c1701
[7] https://lore.kernel.org/dri-devel/Zfsj0_tb-0-tNrJy@cassiopeiae/