OpenAI on NVIDIA Ada
Can I run gpt-oss 20B-A3.6B on an RTX 4060 Ti 16GB?
Yes. gpt-oss 20B-A3.6B at Q4_K_M uses 13.1 GB of the 14.2 GB available on a RTX 4060 Ti 16GB, and runs at about 62.2 tokens per second. You can push the context to 33K.
Fits, but tight
13.1 GB of 14.2 GB · 92%014 GB
Weights
11.9 GB
KV cache
0.4 GB
Runtime overhead
0.8 GB
This fits with almost nothing to spare. A background application claiming VRAM will push it over. Drop to the next quantisation down, or quantise the KV cache to Q8_0 — that halves the cache for no meaningful quality loss.
Generation62.2tok/s
Prompt processing2567tok/s
Max context33Ktokens
KV per 1K tokens0GB
Every quantisation of gpt-oss 20B-A3.6B on a RTX 4060 Ti 16GB
Highlighted row is the highest quality that still fits at 8K context.
| Quantisation | bpw | Weights | Total | Verdict | Max ctx | tok/s |
|---|---|---|---|---|---|---|
| FP16 / BF16 | 16.00 | 38.9 GB | 40.1 GB | Won't fit | — | 7.32 |
| INT8 / W8A8 | 8.50 | 20.4 GB | 21.6 GB | Won't fit | — | 18.9 |
| FP8 (E4M3) | 8.00 | 19.5 GB | 20.6 GB | Won't fit | — | 20.9 |
| Q6_K | 6.56 | 16.0 GB | 17.1 GB | Won't fit | — | 30.6 |
| Q5_K_M | 5.67 | 13.8 GB | 15.0 GB | Won't fit | — | 44.6 |
| Q5_K_S | 5.52 | 13.4 GB | 14.6 GB | Won't fit | — | 50.3 |
| AWQ 4-bit | 4.25 | 11.9 GB | 13.1 GB | Fits, but tight | 32K | 62.1 |
| GPTQ 4-bit | 4.25 | 11.9 GB | 13.1 GB | Fits, but tight | 32K | 62.1 |
| MXFP4 | 4.25 | 11.9 GB | 13.1 GB | Fits, but tight | 32K | 62.1 |
| Q4_K_M | 4.85 | 11.9 GB | 13.1 GB | Fits, but tight | 33K | 62.2 |
| Q4_K_S | 4.58 | 11.3 GB | 12.4 GB | Runs comfortably | 46K | 65.1 |
| Q4_0 | 4.55 | 11.2 GB | 12.4 GB | Runs comfortably | 48K | 65.5 |
| IQ4_XS | 4.25 | 10.5 GB | 11.7 GB | Runs comfortably | 63K | 69.1 |
| Q3_K_M | 3.91 | 9.7 GB | 10.9 GB | Runs comfortably | 79K | 73.7 |
| IQ3_M | 3.70 | 9.2 GB | 10.4 GB | Runs comfortably | 89K | 76.9 |
| IQ3_XXS | 3.06 | 7.8 GB | 8.9 GB | Runs comfortably | 121K | 88.5 |
| Q2_K | 2.63 | 6.8 GB | 8.0 GB | Runs comfortably | 128K | 98.5 |
| IQ2_XXS | 2.06 | 5.5 GB | 6.7 GB | Runs comfortably | 128K | 116 |
| IQ1_M | 1.75 | 4.8 GB | 5.9 GB | Runs comfortably | 128K | 128 |