NVIDIA DGX Spark vs NVIDIA RTX 3080 20GB for local LLMs
87 reports on the NVIDIA DGX Spark and 14 on the NVIDIA RTX 3080 20GB
Which is faster for local LLMs?
On Qwen3.8 27B at 4-bit, the NVIDIA DGX Spark has generation speed not reported; prompt processing 899.9 tokens/s (one run); the NVIDIA RTX 3080 20GB has 25.7 generation tokens/s (2 runs); prompt processing 997.0 tokens/s (one run). Memory bandwidth, which caps how fast a card can write, is 2.8x higher on the NVIDIA RTX 3080 20GB (273 GB/s on the NVIDIA DGX Spark, 760 on the NVIDIA RTX 3080 20GB).
- Memory
- 128GB unified
- Memory bandwidth
- 273 GB/s
- FP16 compute
- 125 TFLOPS
- Reports
- 87
- Memory
- 20GB
- Memory bandwidth
- 760 GB/s
- FP16 compute
- 119 TFLOPS
- Reports
- 14
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 DGX Spark | NVIDIA RTX 3080 20GB |
|---|---|---|
| Qwen3.8 27B4-bit | -0 runsPP 899.9 (one run)llama.cpp16K context | 25.72 runsPP 997.0 (one run)llama.cpp, 1 not stated96K context, 1 not stated |
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 DGX Spark | NVIDIA RTX 3080 20GB |
|---|---|---|
| Qwen3.8 27B | 4.0 t/sFP16 | 35.4 t/sQ3_K_M |
| Qwen3.8 125B · 6B active | 14.4 t/sQ6_K | 19.1 t/sQ2_K, experts in RAM |
| Qwen3.6 35B · 3B active | 14.5 t/sFP16 | 140.5 t/sQ3_K_S |
| DeepSeek V4 Flash 284B · 13B active | 38.3 t/sQ2_K | doesn't fit at these settings |
| Qwen3.6 27B | 4.0 t/sFP16 | 35.4 t/sQ3_K_M |
| Gemma 4 26B · 4B active | 10.8 t/sFP16 | 79.7 t/sQ4_K_S |
| GLM-5.3 320B · 18B active | 12.7 t/sQ2_K | doesn't fit at these settings |
Change the context, RAM or model in the calculator: NVIDIA DGX Spark · NVIDIA RTX 3080 20GB
Every report on each card, with its source: NVIDIA DGX Spark · NVIDIA RTX 3080 20GB