Gemma 4 31B is a 31.27B-parameter model. At Q4_K_M it needs about 19.1 GB of memory. The AMD RX 7900 XT 20GB has 19 GB usable, so it only fits with part of the model offloaded to system RAM, which slows it down. Expect about 26 tokens/sec (10–43), with the first token after 1.6 s for a short prompt. This estimate is projected from the hardware specs; no benchmarks exist yet.
| Quantization | File size | Memory | Generation | First token | Source |
|---|---|---|---|---|---|
| Q4_K_M | 18.3 GB | Partial offload | 26 tok/s | 1.6 s | Projected |
| Q8_0 | 32.6 GB | Partial offload | 3.8 tok/s | 1.6 s | Projected |
| FP16 | 61.4 GB | Doesn't fit | Won't run | — | — |
All models on the AMD RX 7900 XT 20GB · Gemma 4 31B on all hardware
Estimates for a short prompt on a single device. Measured numbers come from community benchmarks (r/LocalLLaMA, localscore.ai and more); others are derived from similar setups or projected from specs. Open source on GitHub.