RTX 5090 meets the minimum VRAM requirement for Q4 inference of Qwen/Qwen3-8B-FP8. Review the quantization breakdown below to see how higher precision settings impact VRAM and throughput.
RTX 5090 can run Qwen/Qwen3-8B-FP8 with Q4 quantization. At approximately 324 tokens/second, you can expect Excellent speed - conversational response times under 1 second.
You have 28GB headroom, which is sufficient for system overhead and smooth operation.
| Quantization | VRAM needed | VRAM available | Estimated speed | Verdict |
|---|---|---|---|---|
| Q4 | 4GB | 32GB | 323.69 tok/s | ✅ Fits comfortably |
| Q8 | 9GB | 32GB | 192.83 tok/s | ✅ Fits comfortably |
| FP16 | 17GB | 32GB | 121.87 tok/s | ✅ Fits comfortably |