Balance speed, memory and capability
Smaller models generally need fewer resources and can respond faster, but may be less capable on demanding tasks. Larger models can handle some tasks better, while requiring more memory and often taking longer to load or generate. Quantization can lower memory use, but does not make hardware limits disappear.
Long context settings also use resources. If a model is slow or fails to load, try closing other GPU-heavy applications, choosing a smaller compatible model, shortening the context, or using CPU inference with realistic expectations.
Local-model answers can still be wrong. A larger model or faster computer does not guarantee factual accuracy.
One measured example
Cursiv's hardware notes report one test computer: an Intel i5-12450HX, 32 GB system RAM and an RTX 2050 with 4 GB graphics memory. For one prompt of about 120 words, qwen3:4b-instruct took 3.7 seconds with GPU inference and 13.4 seconds on processor only; qwen2.5:1.5b took 2.6 and 8.3 seconds respectively.
These are single-machine measurements with the model already loaded for the reported response. They do not predict performance on other computers. Read the full measurement notes.