You're my last hope - NVIDIA driver broke my HDMI 2.1 EDID on Samsung TV - please!

[kurant]

Hello,

First of all, NVIDIA said they couldn't replicate the issue which is just a slap into my face. I sent them dispdiay, dxdiag, everything. Maybe you can help?

Short version first:

The issue is driver-related and has existed since 577.00 up to the current 591.74.
Starting with driver 577.00, it is physically impossible to properly connect a Samsung TV with Game Mode enabled via HDMI.

- With driver 577.00, everything works fine (HDMI 2.1 Game Port and Samsung Game Mode Enabled).
- With driver newer than 577.00 (eg. 591.74), Samsung Game Mode doesn't work with Game Port 2.1 HDMI.
- The same TV worked perfectly on an RX 9070 XT on all drivers.
- TV: Samsung The Frame 2024 75", connected via HDMI 2.1.

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Longer version:

I did some deeper testing and I think the results might be genuinely useful for NVIDIA to reproduce this HDMI/EDID. Before each driver install I removed the previous driver in Windows Safe Mode (clean uninstall), and I also did that before switching HDMI ports.

What I found (three scenarios)

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Driver 577.00 (clean install) + OneConnect “gamepad” port + Game Mode ON

- Everything works perfectly
- TV is detected properly
- Proper EDID / CRU shows a full, correct configuration (multiple extension blocks)
- 4K works correctly, games get native resolution
- Aspect ratio is correct
- VRR Game Mode behaves as expected

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Driver 591.74 (clean install) + OneConnect “gamepad” port + Game Mode ON

- TV becomes basically unusable
- In NVIDIA Control Panel the display shows up as a generic “Digital Monitor”
- Windows can’t properly detect the display (no native resolution, resolution options are broken)
- CRU “active” looks empty / no proper EDID data (as if there’s no real EDID handshake)
- Random “unsupported resolution” errors on the TV
- G-Sync not working
- No native 4K option in games
- Games rendering in wrong aspect ratios (e.g. widescreen)
- On reboot with both monitor and TV connected, the screen just flickers

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Driver 591.74 (clean install) + switching HDMI from “gamepad” HDMI 2.1 port to another OneConnect HDMI port (2.0) + Game Mode ON

- Moving the same HDMI cable from the dedicated “gamepad” port (HDMI 2.1) to a different port (e.g. HDMI 3 2.0) makes the TV work again
- 4K and 120 Hz works, VRR/Game Mode works
- BUT: output format becomes limited (YCbCr 4:2:0 + Limited range),
- In CRU the “active” EDID/extension block structure is different (simpler) compared to the gamepad port on 577.00

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This strongly suggests the bug is tied to the EDID/CTA extension handling or HDMI 2.1 handshake path when Samsung Game Mode is enabled on the dedicated gaming port (HDMI 2.1). The same TV + OneConnect worked flawlessly on an AMD GPU (RX 9070 XT) across drivers, including Game Mode. With NVIDIA, the problem appears after driver 577.00 and persists to newest.

I'd love to see some input here.