CanRun

Can I run Qwen3 32B on the GeForce RTX 4090?

Runs greatQ4_K_M fits in VRAM with 1.4 GB to spare: Runs great, 42.5 tok/s measured at 512 context (1 run; 8k estimate 32.2 tok/s, 28.3–36.1, calibrated estimate ±12%).

24 GB VRAM · 1,008.0 GB/s · FP16 82.6 TFLOPS. Assumes 32 GB of DDR5-5600 system RAM, Windows with this GPU driving the display, 8k context and an f16 KV cache. The verdict and quant file above stay the same anywhere from 16 to 128 GB of system RAM. The GeForce RTX 3090 Ti has the same memory setup (24 GB, 1,008.0 GB/s), so its generation-speed estimate is the same; only prompt processing differs. Prompt processing: about 2,722 tok/s (1,633–3,811, rough estimate ±40%) here vs about 1,318 tok/s (791–1,845, rough estimate ±40%) on the GeForce RTX 3090 Ti.

Every quant of Qwen3 32B on the GeForce RTX 4090

4 tracked GGUF files, smallest first, at 32 GB of system RAM and 8k context
QuantFile sizeVerdictSpeedMemoryRuns asNotes
Q2_K12.34 GBRuns great
est. 48.7 tok/s42.9–54.5calibrated estimate ±12%
15.4 / 24.0 GBFull GPU—
IQ4_XS17.69 GBRuns great
est. 35.6 tok/s31.3–39.8calibrated estimate ±12%
20.6 / 24.0 GBFull GPU—
Q4_K_Mbaseline19.76 GBRuns great
42.5 tok/s8k estimate 32.2 tok/s (28.3–36.1, calibrated estimate ±12%)measured (1 run, 512 context)
22.6 / 24.0 GBFull GPU—
Q8_034.82 GBWon't run
est. 2.7 tok/s2.2–3.3calibrated estimate ±20%
24.0 / 24.0 GB + 14.1 GB RAMPartial offloadFits, but too slow to use

Models with a thinking mode spend extra tokens thinking, so their speed thresholds are 1.5× stricter (30 / 12 / 3 tok/s). With thinking turned off, a model may do one grade better.

Where the memory goes at Q4_K_M

Weights, KV cache and compute buffer are the model; the OS reservation is the display driver.
GPU memory
Weights
19.3 GB
KV cache
2.1 GB
Compute buffer
0.6 GB
OS reserve
0.6 GB
Free
1.4 GB

0.44 GB of the 19.76 GB file stays off the graphics card: llama.cpp keeps the input embedding table in system RAM.

Context length vs. KV cache

KV cache

Memory needed and verdict at Q4_K_M for each context length and KV cache type, with estimated tokens per second.
ContextKV f16KV q8_0KV q4_0
4k
20.9 GBRuns great
est. 33.9 tok/s29.8–37.9calibrated estimate ±12%
20.4 GBRuns great
est. 34.7 tok/s30.5–38.9calibrated estimate ±12%
20.2 GBRuns great
est. 35.2 tok/s30.9–39.4calibrated estimate ±12%
8k
22.0 GBRuns great
42.5 tok/s8k estimate 32.2 tok/s (28.3–36.1, calibrated estimate ±12%)measured (1 run, 512 context)
21.0 GBRuns great
est. 33.7 tok/s29.7–37.8calibrated estimate ±12%
20.5 GBRuns great
est. 34.6 tok/s30.5–38.8calibrated estimate ±12%
16k
24.3 GBRuns well
est. 14.9 tok/s11.9–17.8calibrated estimate ±20%
22.3 GBRuns great
est. 32.0 tok/s28.2–35.8calibrated estimate ±12%
21.2 GBRuns great
est. 33.6 tok/s29.6–37.7calibrated estimate ±12%
32k
28.7 GBRuns slowly
est. 4.7 tok/s3.8–5.6calibrated estimate ±20%
24.7 GBRuns well
est. 12.5 tok/s10.0–15.0calibrated estimate ±20%
22.6 GBRuns great
est. 31.8 tok/s28.0–35.6calibrated estimate ±12%

S = Runs great · A = Runs well · B = Runs slowly · F = Won't run

At Q4_K_M the verdict stays Runs great up to 8k context with an f16 KV cache, and up to 16k with q8_0.

Estimated speed

Generation
42.5 tok/s measured at 512 context (1 run; 8k estimate 32.2 tok/s, 28.3–36.1, calibrated estimate ±12%)
Prompt processing
about 2,722 tok/s (1,633–3,811, rough estimate ±40%)

Measured on this exact combination

Public benchmarks we calibrate against. Their conditions (context, backend, flags) can differ from the estimates above.

Measured on this exact combination
HardwareQuantBackendContextPrompt (tok/s)Generation (tok/s)FlagsSourceMeasured
GeForce RTX 4090Q4_K_XLllama.cpp4k2,448.039.6CUDAhardware-corner.net2026-03-01
GeForce RTX 4090Q4_K_Mllama.cpp5122,302.042.5Vulkangithub.com2025-12-09

If this is not enough

How to run it

Commands for the Q4_K_M file. Both tools download from Hugging Face on first run.

File: Qwen_Qwen3-32B-Q4_K_M.gguf (19.76 GB) from bartowski/Qwen_Qwen3-32B-GGUF.

llama.cpp
llama-server -hf bartowski/Qwen_Qwen3-32B-GGUF:Q4_K_M -c 8192 -ngl all -fa on
  • -ngl all loads every layer on the GPU.
  • -fa on enables flash attention (needed for KV cache quantization).
  • --cache-type-k q8_0 --cache-type-v q8_0 shrinks the KV cache to 1.15 GB at 8k context.
Ollama

PowerShell (quit the Ollama tray app first):

$env:OLLAMA_CONTEXT_LENGTH="8192"; ollama serve
ollama run hf.co/bartowski/Qwen_Qwen3-32B-GGUF:Q4_K_M
  • Ollama defaults to 4k context on GPUs under 24 GB. Set OLLAMA_CONTEXT_LENGTH when starting the server, or /set parameter num_ctx inside the chat.
  • /set parameter num_ctx 8192

Related pages

Frequently asked questions

Can I run Qwen3 32B on the GeForce RTX 4090?

Q4_K_M fits in VRAM with 1.4 GB to spare: Runs great, 42.5 tok/s measured at 512 context (1 run; 8k estimate 32.2 tok/s, 28.3–36.1, calibrated estimate ±12%). Q4_K_M needs 22.0 GB at 8k context; this setup has 23.4 GB of usable memory and 28.0 GB of free system RAM.

How much context can Qwen3 32B use on the GeForce RTX 4090?

At Q4_K_M the verdict stays Runs great up to 8k context with an f16 KV cache (2.1 GB of KV) and up to 16k with a q8_0 KV cache (2.3 GB). The model supports up to 32k.

Which quant should I use, and how fast is it?

Q4_K_M (19.76 GB) is the recommended balance: Runs great, 42.5 tok/s measured at 512 context (1 run; 8k estimate 32.2 tok/s, 28.3–36.1, calibrated estimate ±12%). It is also the largest tracked file that gets this verdict.

Speeds are estimates from memory bandwidth, calibrated against public benchmarks, and each one comes with an error band and a confidence label. Real results vary with drivers, backend, context length and thermals.