SupraGSX wrote on 2025-12-04, 05:58:

Fixed with following method. […]
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Fixed with following method.

The root cause is the EDID modern monitors expose, which XP interprets incorrectly.
Fixing the EDID so XP detects HDMI-HDTV enables Nvidia’s HDMI audio device.

This method is tested on an Alienware AW3423DW, but should apply to any modern display that's recognized as DVI

1. Ensure UAA HD Audio Driver Is Installed (Required for Audio Enumeration)

Windows XP SP3 does not include a working UAA HD Audio driver.
The original KB888111 patch only installs on SP2.

You need the patched SP3 version so XP can enumerate HD Audio devices such as:

HDAUDIO\FUNC_01&VEN_10DE (Nvidia HDMI audio)

Once installed, confirm the bus driver:

C:\Windows\System32\drivers\hdaudbus.sys

If UAA is not installed, HDMI audio will never appear — regardless of EDID fixes.

2. Install Nvidia Display Driver and Nvidia HD Audio Driver (Any Known Working Method)

You must have:

A functioning display driver (e.g., 355.98)

A functioning Nvidia HD Audio driver (e.g., from 344.11)

This guide assumes the user already knows how to install these manually through Device Manager.

At this stage, the Nvidia HD Audio driver can be installed but XP still won't let you select it as playback device.

3. The Real Problem: XP Thinks Your HDMI Display is DVI

4. Solution: Override the EDID With a Correct HDMI + Audio Version

You must provide XP with an EDID override that includes:

A valid CEA Extension Block

HDMI capability flag

Audio Data Block (LPCM 2ch @ 32/44/48 kHz)

No HDR metadata

A native timing XP/Nvidia can handle

There are two ways to create this EDID:

Phoenix EDID Designer

Edit the existing EDID
– Add CEA block
– Add HDMI bits
– Add audio
– Remove HDR
– Set native timing
Export as .bin

Create a monitor INF (required for Windows XP)

XP cannot load .bin EDIDs directly.
You must embed the EDID inside a monitor driver INF.

The INF supplies:

HKR,"EDID_OVERRIDE",...
HKR,,VideoInterfaceType=2 ; Forces HDMI

Once installed, XP prefers this EDID over the physical EDID.

5. Install the EDID Override INF in Windows XP

1. Device Manager → Monitors

2. Right-click your monitor → Update Driver

3. “Install from a list or specific location”

4. “Don’t search. I will choose”

5. Have Disk…

6. Browse to your EDID override INF

7. Install → reboot

After reboot, XP should show the connector as: HDMI-HDTV and audio should be working.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\

Can you dump this reg key to a file?
I'm moderately sure, somewhere in there, the EDID things you did will show up.

In which case, it can probably be made generic, one click reg, inf, or bat.

SupraGSX wrote on 2025-12-04, 05:58:

Fixed with following method.

Besides SupraGSX, has anyone managed to get HDMI sound on a GTX 980ti? I couldn't, but maybe I'm misunderstanding the instructions - I'm using Google Translator.

Basically:
Write a "driver" inf for your SCREEN that you manually install that says "I am a HDMI monitor with sound".
Using a tool.

I think it might be possible to convert to a single reg key to rule them all, but I need someone with it working in XP to give me the reg keys to see if I can figure out the magic.

Will my reg file work? Or are you referring to the modified registry from SupraGSX? If my file helps, you can find it here:
https://drive.google.com/file/d/1w3dotuTjL2dT … iew?usp=sharing

The modified working one.

https://github.com/SupraGSX/Forceware-382.69

This driver fixes this and adds pascal support.

Which pascal cards have you tested?

1080ti and p4000

I kinda have to see this.
Afik 10 was a serious architectural change, and no one in 15 years has figured out how to get it working on xp.

Got some gpuz + dxdiag + furmark/bench pics?

SupraGSX wrote on 2026-09-27, 15:24:

https://github.com/SupraGSX/Forceware-382.69

This driver fixes this and adds pascal support.

Wowzers, is that the driver Omores mentioned?
I'd like to test it on 1060.

It might be better to start a new thread for the Pascal XP driver.

Yes it's that driver. I shared with him a few days ago haven't heard back if it worked for him. As I said above I used my p4000 and 1080ti as test GPU so those are the only two I guarantee work but it should work for everything but gp108. Let me know how it goes.

myne wrote on 2026-09-29, 05:30:

I kinda have to see this.
Afik 10 was a serious architectural change, and no one in 15 years has figured out how to get it working on xp.

Got some gpuz + dxdiag + furmark/bench pics?

Not true at all 368.81 had every pascal branch already in it don't know if they planned on doing a pascal release or the unified driver structure just inherited it. But it was always there. To get gp104 working was only adding two display calls that's it. For gp102 it used a some newer tables for sec2/acr but I backported that from the first win7 driver with 1080ti support I forget which one maybe 376? But doing that and redirecting maybe 6 calls is all it took. Was a very simple backport. The open source nouveau Linux drivers gave a complete picture of driver calls on both pascal and Maxwell. So using those as a guide made it easy to know what drivers need newer tables. Thats the only reason I'm saying gp108 won't work it has newer tables in the open source drivers that I know this driver doesn't have. Getting hbr3 working was more difficult than pascal by itself.

You can watch the video that was linked to omores video above if you want to see it. Its the last 1 minute or so of the video. That PC build is a x870e apex board with 9950x3d, voodoo3 custom PCie card, 1080ti, and 4090 with cmi8738 for sound. Boots every os from dos to win11 and Linux is my daily driver. I only did 1080ti driver because I hated sacrificing win7 performance on a Maxwell card.

Also if you explore my other GitHub repo the Native CSM VGA Selector is built specifically to fix OS like winxp and win98 needing the GPU it boots with to be seen as primary. Most manufacturers don't provide the option to boot a non primary vga adapter anymore. So for a build like this to work I had to create that.