Can the RX 7900 XTX 24 GB run MiniMax H3 (33B)?
Download Q3_K_M (15.6 GB). With the model's working memory it needs about 21.4 GB, leaving 2.6 GB spare on 24 GB. Quality: noticeable loss of detail. For better quality, Q4_K_M (19.9 GB) also runs, with about 1.7 GB spilling into system RAM — a little slower, still practical.
01What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Model | MiniMax-H3-FL2VA-Q3_K_M.gguf Q3_K_M · Abiray/MiniMax-H3-GGUF | models/unet | 15.6 GB | Download → |
| Text encoder | qwen3vl_32b_minimax_h3_int8_convrot.safetensors Qwen3-VL 32B INT8 (convrot) · Comfy-Org/MiniMax-H3 | models/text_encoders | 27.1 GB | Download → |
| VAE | minimax_h3_video_vae_fp16.safetensors MiniMax H3 video VAE FP16 · Comfy-Org/MiniMax-H3 | models/vae | 5.2 GB | Download → |
| Also needed | minimax_h3_audio_vae_fp32.safetensors MiniMax H3 audio VAE FP32 · Comfy-Org/MiniMax-H3 | models/vae | 0.6 GB | Download → |
| Total download · keep about the same free on disk | 48.5 GB | |||
Alternatives: Qwen3-VL 32B NVFP4 (AWQ) (15.7 GB); Qwen3-VL 32B BF16 (51.5 GB). The 16-bit text encoder is a little more faithful; the smaller one is chosen here because it loads faster and needs less RAM. FP4 files are listed only as alternatives unless the GPU is an RTX 50 (Blackwell). Sizes read from Hugging Face (2026-09-25). “Download” links start the file directly; the file name links are the same files the official ComfyUI workflows use.
System RAM: 64 GB or more. ComfyUI keeps the model file, the text encoder and the VAE in system RAM and moves them to the GPU as needed. With this set of files that is about 48.5 GB, plus roughly 6 GB for Windows, ComfyUI and a browser: 54.5 GB in total. With less RAM it still runs, but Windows starts swapping to disk and loading gets very slow. calculated
02Every MiniMax H3 file on 24 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit SAFETENSORS · Comfy-Org | 66.3 GB | 72.1 GB | 48.1 GB too big | the original weights | Hugging Face → |
| Q8_0 GGUF · Abiray | 36.0 GB | 41.8 GB | 17.8 GB too big | practically identical to the original | Hugging Face → |
| INT8 SAFETENSORS · Comfy-Org | 34.0 GB | 39.8 GB | 15.8 GB too big | practically identical to the original | Hugging Face → |
| Q6_K GGUF · Abiray | 28.2 GB | 34.0 GB | 10.0 GB too big | very close to the original | Hugging Face → |
| Q5_K_M GGUF · Abiray | 23.9 GB | 29.7 GB | 5.7 GB too big | close; small differences in fine detail | Hugging Face → |
| Q4_K_M GGUF · Abiray | 19.9 GB | 25.7 GB | spills 1.7 GB | good; some loss in fine detail and text | Hugging Face → |
| Q3_K_M ← GGUF · Abiray | 15.6 GB | 21.4 GB | fits · 2.6 GB spare | noticeable loss of detail | Hugging Face → |
Sizes from the Hugging Face file listing, read 2026-09-25. “Needed” = file + 5 GB working memory for this model + 0.8 GB kept free for the system.
03The text encoder
Qwen3-VL 32B: 51.5 GB as 16-bit, 27.1 GB as INT8, 15.7 GB as NVFP4. ComfyUI encodes the prompt first and can push the encoder out of VRAM before sampling, so it does not have to fit together with the model. Use the smallest encoder file; it still fits on its own.
04About this GPU
ComfyUI supports AMD GPUs on Windows officially since v0.7.0 (January 2026), through ROCm. Memory works the same as on NVIDIA, so the fit verdicts apply. Some custom nodes are NVIDIA-only. RDNA 3 has no FP8 compute, so FP8 files save memory but give no speed-up.
RX 7900 XTX 24 GB: 24 GB GDDR6 · 384-bit · 960 GB/s · RDNA 3. Everything that runs on the RX 7900 XTX 24 GB →
05What more VRAM would change
With 48 GB you could run MiniMax H3 at 8-bit or better (Q8_0, 36.0 GB) with no offloading.
What changes from the RX 7900 XTX 24 GB to the RTX 5090 32 GB →
06Measured and reported results
Nobody has sent measured numbers for this pair yet. If you run MiniMax H3 on a RX 7900 XTX 24 GB, send your time per image and peak VRAM and it will appear here, credited.
07Questions
How much VRAM does MiniMax H3 need?
Around 21.4 GB with the smallest file (Q3_K_M) and 39.8 GB with an 8-bit file (INT8), counting working memory and a small system reserve. The full 16-bit file needs about 72.1 GB.
Which MiniMax H3 file should I download for the RX 7900 XTX 24 GB?
Q3_K_M (15.6 GB) from Abiray/MiniMax-H3-GGUF. Load it with Unet Loader (GGUF) from the ComfyUI-GGUF node pack.
Is FP8 faster than GGUF on the RX 7900 XTX 24 GB?
No. This GPU has no FP8 compute, so ComfyUI converts FP8 weights back before the maths. FP8 only saves memory here; Q8_0 GGUF is the closer-to-original 8-bit pick.
How much do I need to download for MiniMax H3 on the RX 7900 XTX 24 GB?
About 48.5 GB for the model file, text encoder and VAE listed on this page, and the same again free on disk. With a 24 GB card, 64 GB of system RAM or more is recommended.