RTX 5090 vs. RTX 5080: which GPU for local AI?
Focused comparison Local LLM : we're looking at what really matters for running models—VRAM above all, then generation speed and price. Purchase verdict at the end.
Updated on 09/10/2026
Comparison at a glance
| Criterion | RTX 5090 | RTX 5080 |
|---|---|---|
| Memory | 32 GB VRAM | 16 GB VRAM |
| Brand | NVIDIA | NVIDIA |
| Compatible models (Q4) | 182 models in the catalog | 143 models in the catalog |
| Largest model (Q4) | Jamba 1.5 Mini (52B) | Qwen 3.8 27B Obliterated (28B) |
Which one should you choose to run an LLM?
Golden rule: with the same budget, always choose the GPU with the most VRAM. A model that exceeds the VRAM limit collapses in speed (CPU offloading). VRAM determines the size of the model; computing power mainly dictates the Speed.
Where to buy (up-to-date pricing and stock)
Alternative purchase: GMKtec EVO-X2 64 GB / 1 TB (Ryzen AI Max+ 395). A mini PC is a complete machine, not a replacement board; check memory and software compatibility.
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Frequently asked questions
RTX 5090 or RTX 5080 for running an LLM locally?
For local use, the VRAM premium. The RTX 5090 (32 GB) runs larger models than the RTX 5080 (16 GB).
What is the largest model the RTX 5090 can run?
Up to Jamba 1.5 Mini (52B) in Q4 quantization, with its 32 GB.
Should you buy used?
For LLMs, a used GPU with more VRAM often beats a newer card with less memory. Check its condition and warranty.