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[BUG] NVEnc / H265 / Tune "UHQ" = incompatible command - Printable Version

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+--- Thread: [BUG] NVEnc / H265 / Tune "UHQ" = incompatible command (/thread-4532.html)

NVEnc / H265 / Tune "UHQ" = incompatible command - tailland - 12.11.2026

version 2026-11-11

problem:
   

"auto" works, "uhq" = crash

RE: NVEnc / H265 / Tune "UHQ" = incompatible command - Selur - 12.11.2026

According to the documentation, that is kind of expected on 'older' cards, but your "NVIDIA GeForce RTX 4070 SUPER", should work fine. :/
Quote:--tune <string>
Extra tuning option to preset.
  • hq (default)
  • uhq
    For HEVC and AV1 only, and requires Turing Gen GPU or later.
  • lowlatency
  • ultralowlatency
  • ossless
    Implicitly enables --lossless.
source: https://github.com/rigaya/NVEnc/blob/master/NVEncC_Options.en.md#--tune-string

I can reproduce the problem on my Geforce RTX 4080.
=> I'll look into it and probably report it to the author of NVEncC.

Cu Selur

RE: NVEnc / H265 / Tune "UHQ" = incompatible command - Selur - 12.11.2026

Got it, UHQ with HEVC failed because Hybrid’s default of 3 B-frames is too few for it.
--tune uhq turns on NVENC’s temporal filter (tfLevel: 4) for HEVC and AV1, and that filter needs at least 4 B-frames.
Hybrid always writes --bframes, and its default is 3, so NVENC rejects the setup with error 8. Testing NVEncC directly:

Tested it on my system.

NVEncC --tune uhq:(RTX 4080, driver 621.14, NVEncC 9.40)

Codec

--bframes 0-3

--bframes 4

--bframes 3 --tf-level 0
HEVC
error 8
works
works
AV1
error 8
works
works
H.264
works
works
works



=> I'll adjust Hybrid to raise bFrames minimum to 4 under uhq (HEVC/AV1). Will report back once I did the fix and uploaded a new dev.

Cu Selur

RE: NVEnc / H265 / Tune "UHQ" = incompatible command - Selur - 12.11.2026

Uploaded a new dev, which fixes the issue here.
Let me know whether that works for you too.

Cu Selur

RE: NVEnc / H265 / Tune "UHQ" = incompatible command - tailland - 12.11.2026

that's an interesting find. cool