NVIDIA RTX 5090 vs AMD RX 7800 XT 16GB for local LLMs
170 reports on the NVIDIA RTX 5090 and 8 on the AMD RX 7800 XT 16GB
Which is faster for local LLMs?
On Qwen3.8 27B at 4-bit, the NVIDIA RTX 5090 has 80.0 generation tokens/s (7 runs); the AMD RX 7800 XT 16GB has 35.0 generation tokens/s (2 runs). Those are community reports whose engines and settings differ, so the gap is a rough sign, not a controlled measure of the two cards. Memory bandwidth, which caps how fast a card can write, is 2.9x higher on the NVIDIA RTX 5090 (1,792 GB/s on the NVIDIA RTX 5090, 624 on the AMD RX 7800 XT 16GB).
- Memory
- 32GB
- Memory bandwidth
- 1,792 GB/s
- FP16 compute
- 419 TFLOPS
- Reports
- 170
- Memory
- 16GB
- Memory bandwidth
- 624 GB/s
- FP16 compute
- 75 TFLOPS
- Reports
- 8
Measured on both
Generation and prompt processing speeds from plain runs (one device, one request, no speculative decoding, the whole model in the device's memory) of the same model size at the same bit class. Each side shows the engines and reported context behind its median. Context can mean a configured window or prompt depth, so these are community comparisons with differing settings. How to read these
| Model | NVIDIA RTX 5090 | AMD RX 7800 XT 16GB |
|---|---|---|
| Qwen3.8 27B4-bit | 80.07 runsllama.cpp, TensorSharp +1, 2 not stated40K to 256K context, 2 not stated | 35.02 runsllama.cpp, 1 not stated100K to 120K context |
Estimated by the calculator
The quant the calculator recommends for each card and its estimated speed at a 32,768-token context with 32 GB of system RAM, from memory bandwidth and the model's shape. Where a model was also measured above, the measurement wins.
| Model | NVIDIA RTX 5090 | AMD RX 7800 XT 16GB |
|---|---|---|
| Qwen3.8 27B | 44.9 t/sQ6_K | 40.7 t/sQ2_K |
| Qwen3.8 125B · 6B active | 20.3 t/sQ2_K, experts in RAM | doesn't fit at these settings |
| Qwen3.6 35B · 3B active | 163.0 t/sQ5_K_M | 134.6 t/sQ2_K |
| DeepSeek V4 Flash 284B · 13B active | doesn't fit at these settings | doesn't fit at these settings |
| Qwen3.6 27B | 44.9 t/sQ6_K | 40.7 t/sQ2_K |
| Gemma 4 26B · 4B active | 114.5 t/sQ6_K | 90.7 t/sQ3_K_S |
| DeepSeek V4.1 Flash 552B · 16B active | doesn't fit at these settings | doesn't fit at these settings |
Change the context, RAM or model in the calculator: NVIDIA RTX 5090 · AMD RX 7800 XT 16GB
Every report on each card, with its source: NVIDIA RTX 5090 · AMD RX 7800 XT 16GB