by the time the 7990 was out I think AMD had stopped supporting crossfire on windows XP, so there is likely no official driver

you could perhaps try forcing the 7970 driver manually?

The PCI ID for the Radeon HD 7990 isn't there, which explains why it doesn't install the display driver.

Try reinstalling it with a .INF modded Catalyst 14.4: https://docs.google.com/uc?export=download&id … MRUKXg2mgNZ2exR Don't forget to run rootsupd.exe (included in the .7z file) if your root certificates are outdated.

WTF? how can AMD release drivers they say support a card and then forget to put the PCI ID in!

I ran setup (which still doesn't work) then installed drivers, ccc manually
the drivers now install but get "This device cannot start code 10"
I noticed even viewer was comapling about Visual C++ not been installed so installed 2010 that's included in the modded package above.
.Net 2.0 is also installed (about the only thing that setup does install)

Apart from that its a clean install XP SP3install with the final DX9 also installed.

I suppose it is typical for AMD to pull that off.
Evidence: I have a Radeon HD 8650G that has no 3D or 2D acceleration under XP SP2 x64, with Catalyst 14.4 installed.

You might have the same issue as I do, albeit in a different form. It might be worth a try to ask somebody here with a Radeon HD 7970 or a Radeon HD 8970 to install Catalyst 14.4 under XP. I don't know for sure if it's due to broken drivers. On my Radeon HD 8650G, it is completely broken. It installs fine without any errors, but it provides no acceleration at all.

Solplay wrote on 2021-02-16, 19:36:

I It might be worth a try to ask somebody here with a Radeon HD 7970 or a Radeon HD 8970 to install Catalyst 14.4 under XP.

That's what I'm doing with this post, seems no one else want to play with me 🙁

Tried fully updating XP with the WSUS Offline installer on the off chance I was missing some dependency. Still no change.
Seems like AMD were talking BS when they said it supported XP

Chinny 22, WHQL drivers 13.4 looked promising but all links for it are "dead ends". Maybe with a more thorough search
you might have better luck than me.

Cool looking card 6GB and all, what size ps you got feeding it?

chinny22 wrote on 2021-02-17, 12:09:

Seems like AMD were talking BS when they said it supported XP

Well, you're not the only one who was fooled. I thought my Radeon HD 8650G had XP support too.

As a last resort, install Catalyst 13.4 or 13.1 with their respective INF mods applied, see how it goes.
CX154613.inf = Catalyst 13.1 - https://docs.google.com/uc?export=download&id … Ppkm50G39-QhtDE
CX160982.inf = Catalyst 13.4 - https://docs.google.com/uc?export=download&id … ePQwMqKvWdSAyCx
Run the installer and wait for it to extract the files, then drag the matching .INF into Packages\Drivers\Display\XP_INF.

The Catalyst drivers can be found here:
Catalyst 13.1 - https://www.philscomputerlab.com/uploads/3/7/ … dd_ccc_whql.exe
Catalyst 13.4 - https://www.philscomputerlab.com/uploads/3/7/ … dd_ccc_whql.exe

By the way, the Radeon HD 7990 and the Radeon HD 8990's PCI ID are not listed in the .INF files. That's why I had to modify them again...

No change I'm afraid, tried both with clean install of windows but still get "This device cannot start code 10"
Thanks for your help Solplay but I'm giving up for now and keep it just as a Win7 box.
If anyone ever does successfully get it working then please do tell me how though!

This is the PC in question, Its a ridiculous build and XP would have made it even more so!
My Win7/XP build with 2 CPU 16 thread's, 4 GPU crossfire, 2 PSU build

nope, it has 6gb of vram, there will never be driver support

It doesn't. That's two cards with 3 Gb VRAM each. Also GeForce GTX Titan works just fine.

Phil did a vid with a 7770 ( I think it was). He got the CCC installed then used the "snappy drivers" thing, to get the driver part installed.

Edit : Found the vid, not the same card but the same problem with the drivers.

https://youtu.be/yTFv4x8srL0