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estimate

Can I run Llama 3.1 8B on a Dual RTX 4090?

Yes, fully in VRAM (estimate)

Can I run Llama 3.1 8B on a Dual RTX 4090? Yes, fully in VRAM (estimate). About 6.7 GB at Q4_K_M (estimate).

Updated . The later of the hardware price date and the formula date.

Llama 3.1 8B on Dual RTX 4090, formula estimate
QuantContextWeightsKVOverheadTotalUsableFitEst. tok/s
Q4 Q4_K_M8,192 tokens4.8 GB estimate1.1 GB estimate0.8 GB estimate6.7 GB estimate46.8 GB estimatefull143 tok/s estimate
Q5 Q5 (~0.71 bytes/param)8,192 tokens5.7 GB estimate1.1 GB estimate0.8 GB estimate7.6 GB estimate46.8 GB estimatefull124 tok/s estimate
Q8 Q88,192 tokens8.6 GB estimate1.1 GB estimate0.8 GB estimate10.5 GB estimate46.8 GB estimatefull88 tok/s estimate
FP16 FP168,192 tokens16.1 GB estimate1.1 GB estimate0.8 GB estimate17.9 GB estimate46.8 GB estimatefull50 tok/s estimate
Q4, longer context32,768 tokens4.8 GB estimate4.3 GB estimate0.8 GB estimate9.9 GB estimate46.8 GB estimatefull93 tok/s estimate

Formula estimate, not a benchmark. Method →

Cheapest catalog option that fits at Q4

GeForce RTX 3060 12GB, used (median of sold listings), €257, dated 2026-10-16. No buy link.

This hardware

$8,206€7,330

price as of 16 Oct 2026

128 GB DDR4 (estimate): $2,754€2,460. From the 16 Oct 2026 fact-check.

rest of system (estimate): $560€500. The total is the GPU price plus the RAM line plus this estimate. It is not a checked system price.

price unverified

GPU line is 2× the used median €2,185 (€4,370), labelled used, from pcprice.watch (https://www.pcprice.watch/gpu-buying-guide/rtx-4090-price-used-and-specs). 128 GB DDR4 (estimate) €2,460, from the 16 Oct 2026 fact-check. Rest of system (estimate) €500. Other parts from €500 in that fact-check. Not a shop listing. DDR5 was not separately priced, so this total uses the sourced 128 GB DDR4 line. The total is the GPU price plus the RAM line plus that rest estimate. It is not a checked system price.

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Llama 3.1 8B on Dual RTX 4090

[![Llama 3.1 8B Q4 on Dual RTX 4090: fits ✓ · est. 143 tok/s (estimate)](https://localllmrig.com/badge/llama-3.1-8b/dual-rtx-4090.svg)](https://localllmrig.com/can-i-run/llama-3.1-8b/dual-rtx-4090?utm_source=badge)

Questions

Can I run Llama 3.1 8B on a Dual RTX 4090?
Yes, fully in VRAM (estimate).
How much memory does Llama 3.1 8B need at Q4?
About 6.7 GB at 8,192 tokens (estimate): 4.8 GB weights, 1.1 GB KV cache, 0.8 GB overhead.
How fast is Llama 3.1 8B on Dual RTX 4090 (estimate)?
About 143 tok/s at Q4 (estimate, not a benchmark).
Llama 3.1 8B on Dual RTX 4090 (estimate) · localLLMrig