Can I run Gemma 4 12B on an RTX 3090?

Yes: Gemma 4 12B needs about 8.98 GB at Q4_K_M with 32K tokens of context, which fits the 24 GB RTX 3090 with 15.0 GB to spare. At 32K the RTX 3090 holds up to Q8_0 (14.6 GB), and Q4_K_M runs up to 256K (full) tokens.

Yes Q4_K_M with 32K tokens of context

Q4_K_M, 32K
8.98 GB
RTX 3090
24 GB, 936 GB/s
To spare
15.0 GB
Tokens/s
57–81 tokens/s

At Q4_K_M with 32K tokens of context it writes about 57–81 tokens/s for one request on an RTX 3090.

Best precision for Gemma 4 12B on an RTX 3090

The most precise setting that leaves at least 0.5 GB free; one that fits with less is marked tight.

ContextBest fitMemoryFreeTokens/s
8K Q8_0 14.2 GB 9.83 GB 36–51
32K Q8_0 14.6 GB 9.42 GB 35–50
128K Q8_0 16.2 GB 7.77 GB 32–45
256K (full) Q8_0 18.4 GB 5.57 GB 28–39

Gemma 4 12B on the RTX 3090 as the context fills

One request, FP16 KV cache, 0.5 GB plus 10% overhead; a minus sign is memory missing, and tight is less than 0.5 GB free.

Context Q4_K_MFreeTokens/sQ8_0FreeTokens/s
4K 8.50 GB 15.5 GB 60–86 14.1 GB 9.90 GB 37–52
8K 8.57 GB 15.4 GB 60–85 14.2 GB 9.83 GB 36–51
16K 8.70 GB 15.3 GB 59–84 14.3 GB 9.69 GB 36–51
32K 8.98 GB 15.0 GB 57–81 14.6 GB 9.42 GB 35–50
64K 9.53 GB 14.5 GB 54–77 15.1 GB 8.87 GB 34–48
128K 10.6 GB 13.4 GB 48–69 16.2 GB 7.77 GB 32–45
256K (full) 12.8 GB 11.2 GB 40–57 18.4 GB 5.57 GB 28–39

Gemma 4 12B on more than one RTX 3090

CardsBest at 32KTokens/sQ4_K_M longestQ4_K_M tokens/sRent per hour
2× (48 GB) BF16 36–52 256K (full) 87–139 $0.54
4× (96 GB) BF16 64–98 256K (full) 133–235 $1.08

Tensor parallel with the combined bandwidth, as in vLLM; llama.cpp splits layers by default and runs at about one card's speed.

Other options

Run Gemma 4 12B on the RTX 3090 with llama-server

llama-server -hf unsloth/gemma-4-12b-it-GGUF:Q4_K_M -c 262144 -np 1

gemma-4-12b-it-Q4_K_M.gguf, 7.1 GB, from unsloth/gemma-4-12b-it-GGUF (checked 2026-09-29). At -c 262144 on the RTX 3090: 12.8 GB of 24 GB, 11.2 GB free. -np 1: one slot, one sliding window.

Questions

Can I run Gemma 4 12B on an RTX 3090?

Yes: Gemma 4 12B needs about 8.98 GB at Q4_K_M with 32K tokens of context, which fits the 24 GB RTX 3090 with 15.0 GB to spare. At 32K the RTX 3090 holds up to Q8_0 (14.6 GB), and Q4_K_M runs up to 256K (full) tokens.

How fast is Gemma 4 12B on an RTX 3090?

At Q4_K_M with 32K tokens of context it writes about 57–81 tokens/s for one request on an RTX 3090.

What does a second RTX 3090 change for Gemma 4 12B?

Two RTX 3090 cards (48 GB in one tensor-parallel group) hold Gemma 4 12B at BF16 with 32K, and Q4_K_M up to 256K (full) tokens, at about 87–139 tokens/s.

Try other settings in the VRAM calculator or the speed calculator. See also Gemma 4 12B VRAM requirements, what LLMs an RTX 3090 can run and every pair, or detect your own GPU. Model data checked .