at-home/run-on/rtx5090-32
What can I run on an RTX 5090 with 32 GB?
Of its 32 GB of VRAM, about 30 GB is left for a model's weights and cache once the driver and the engine have taken theirs. The largest model below that runs with room for a 8K conversation is Qwen3 32B at Q6_K, decoding at up to 53 tokens a second.
| Model | Best fit | Download | Longest context | Decode, up to |
|---|---|---|---|---|
| Llama 3.2 3B | Q8_0 | 3.4 GB | 226K tokens | 422 tok/s |
| Qwen3.5 4B | Q8_0 | 4.3 GB | 767K tokens | 337 tok/s |
| Llama 3.1 8B | Q8_0 | 8.5 GB | 160K tokens | 169 tok/s |
| Qwen3 8B | Q8_0 | 8.7 GB | 141K tokens | 165 tok/s |
| Qwen3.5 9B | Q8_0 | 9.6 GB | 609K tokens | 150 tok/s |
| Qwen3 14B | Q8_0 | 15.7 GB | 85K tokens | 91 tok/s |
| gpt-oss 20B | MXFP4, as shipped | 12.8 GB | 683K tokens | 112 tok/s |
| Qwen3 32B | Q6_K | 26.9 GB | 12K tokens | 53 tok/s |
| Llama 3.3 70B | does not fit |
Best fit is the highest-quality quantisation that still leaves room for a 8K context. It stops at Q8 rather than FP16, because Q8 is indistinguishable from FP16 in practice and reads half the bytes, so it decodes about twice as fast on a machine like this.
Decode is a ceiling: 80% of this machine’s 1792 GB/s divided by the bytes a token reads, at the start of a conversation. On a measured 16 GB MacBook Air that arithmetic predicted 35.6 tokens a second and MLX delivered 31.4; llama.cpp delivered 17 on the same model. Expect your engine to land at or below it.
Longest context assumes an unquantised KV cache. Quantising the cache to Q8 roughly doubles it. Reading a long prompt also needs working memory the table does not count, so leave a margin.
Read next
- at-home/
- explainers/
- run-on/