AMD · consumer

Radeon RX 7900 XT

Radeon RX 7900 XT has 20 GB of VRAM at 800 GB/s — about 18.60 GiB usable after driver and compositor overhead. 1793 of 2118 indexed models fit at 128K context with q4_0 KV.

Spec sheet· bandwidth, theoreticalFrom the file· fit from summed bytesPredicted· speed
Memory
20 GB
GDDR6
Bandwidth
800 GB/s
320-bit bus
Tensor FP16
dense
TDP
315 W
$899 MSRP
KV cachef16q8_0q4_0quantizing the KV cache is a ~2× lever on the dominant term at long context
text 1520vision language 170audio asr 39video 16image 1embedding 26audio tts 21

What fits at 128K context

largest quantization that fits, per model · 1793 of 2118 indexed
ModelBest quantParamsWeightsKVTotal in memoryHeadroomtok/s
dolphin-2.6-mixtral-8x7bMoEI1-IQ2_S46.7B13.16 GiB4.50 GiB18.59 GiB0.01 GiB34±37%
xLAM-8x7b-rMoEIQ2_S46.7B13.16 GiB4.50 GiB18.59 GiB0.01 GiB34±37%
Muse-Glimmer-30BQ4_K_M29.8B17.13 GiB0.48 GiB18.59 GiB0.01 GiB28±26.5%
Fallen-Gemma3-27B-v1Q4_K_M27.4B15.41 GiB2.23 GiB18.58 GiB0.02 GiB28±26.5%
Qwen3.6-35B-A3B-uncensored-hereticMoEQ3_K_L35.1B16.97 GiB0.70 GiB18.57 GiB0.03 GiB112±37%
Nex-N2-mini-ultra-uncensored-hereticMoEQ3_K_L35.1B16.97 GiB0.70 GiB18.57 GiB0.03 GiB112±37%
c4ai-command-r-08-2024Q2_K32.3B11.93 GiB5.63 GiB18.57 GiB0.03 GiB28±26.5%
KAT-Coder-V2.5-DevMoEUD-IQ4_XS34.7B16.96 GiB0.70 GiB18.57 GiB0.03 GiB112±37%
Qwen3.6-35B-A3BMoEUD-IQ4_XS36.0B16.96 GiB0.70 GiB18.57 GiB0.03 GiB112±37%
Qwen3.5-21B-Claude-4.6-Opus-Deckard-Heretic-Uncensored-ThinkingI1-Q6_K21.3B15.91 GiB1.69 GiB18.56 GiB0.04 GiB28±26.5%
Qwen3.6-21B-IQ-Ultra-Heretic-Uncensored-ThinkingI1-Q6_K21.3B15.91 GiB1.69 GiB18.56 GiB0.04 GiB28±26.5%
medgemma-27b-itI1-Q4_K_S28.8B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
gemma-3-27b-it-abliterated-refined-visionI1-Q4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
gemma-3-27b-it-abliteratedQ4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
Nidum-Gemma-3-27B-it-UncensoredI1-Q4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
gemma-3-27b-itQ4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
AtomicGPT-gemma3-27bI1-Q4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
Unbound-v1.12.0-27BI1-Q4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
Mira-v1.12-Ties-27BI1-Q4_K_S27.4B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
Medgamma27BI1-Q4_K_S27.0B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
medgemma-27b-text-itQ4_K_S27.0B14.60 GiB2.98 GiB18.56 GiB0.04 GiB28±26.5%
GLM-4.7-Flash-Claude-Opus-4.5-High-Reasoning-DistillMoEIQ4_NL31.2B15.79 GiB1.86 GiB18.56 GiB0.04 GiB71±37%
grug-27bQ4_K_S27.4B15.34 GiB2.25 GiB18.56 GiB0.04 GiB28±26.5%
Carnice-V2-27bQ4_K_S27.4B15.34 GiB2.25 GiB18.56 GiB0.04 GiB28±26.5%
Fara1.5-27BQ4_K_S27.4B15.34 GiB2.25 GiB18.56 GiB0.04 GiB28±26.5%
Skyfall-31B-v4.2-hereticI1-IQ2_M31.4B9.94 GiB7.59 GiB18.55 GiB0.05 GiB28±26.5%
Skyfall-31B-v4.2I1-IQ2_M31.4B9.94 GiB7.59 GiB18.55 GiB0.05 GiB28±26.5%
Devstral-Small-2-24B-Instruct-2512IQ4_XS24.0B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Mistral-Small-3.2-24B-Instruct-2506IQ4_XS24.0B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Devstral-Small-2507IQ4_XS23.6B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Devstral-Small-2505IQ4_XS23.6B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Magistral-Small-2509IQ4_XS24.0B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Magistral-Small-2507IQ4_XS23.6B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Mistral-Small-3.1-24B-Instruct-2503IQ4_XS24.0B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Magistral-Small-2506IQ4_XS23.6B11.90 GiB5.63 GiB18.55 GiB0.05 GiB28±26.5%
Gemma-3-27B-MeditronFOIQ4_XS28.8B14.57 GiB2.98 GiB18.53 GiB0.07 GiB28±26.5%
Voxtral-Small-24B-2507IQ4_XS24.3B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Transformed-Journey-24BI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Magistry-24B-v1.1I1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Mergedonia-AETHER-24B-v1aI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Mergedonia-AETHER-24B-v1bI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Slimaki-Tavern-24B-v1.3I1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Maginum-Cydoms-24BI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Maginum-Cydoms-24B-absolute-heresyI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Morax-24B-v2IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Dolphin3.0-R1-Mistral-24BIQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Dolphin3.0-Mistral-24BIQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Mistral-Small-3.2-24B-Instruct-2506-ultra-uncensored-hereticI1-IQ4_XS24.0B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Huihui-Mistral-Small-3.2-24B-Instruct-2506-abliterated-llamacppfixedI1-IQ4_XS24.0B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Dans-PersonalityEngine-V1.2.0-24bI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Mistral-Small-3_2-24B-Instruct-2506-antislop.v2I1-IQ4_XS24.0B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Cydonia_VistralIQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Dans-PersonalityEngine-V1.3.0-24bI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Goetia-24B-v1.1I1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
MS3.2-PaintedFantasy-v3-24BI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
RP-Spectrum-24BI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
MS3.2-PaintedFantasy-v4.1-24B-ultra-uncensored-heretic-v2I1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Magidonia-24B-v4.3-heretic-v1.2I1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
Magidonia-24B-v4.3-absolute-heresyI1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
MagiSeek-Pro-V1I1-IQ4_XS23.6B11.88 GiB5.63 GiB18.53 GiB0.07 GiB29±26.5%
From the filePredictedwhat these mean

Speed is modeled, not measured: decode is memory-bandwidth bound, so tokens per second is bytes read per token against achievable bandwidth. Mixture-of-experts models carry a wider band because only the routed experts are read each step, and few have been measured publicly.

Measured on this card

third-party benchmarks, aggregated
WorkloadMedianMiddle 50%Runs
Image generation11.45 it/s7.7516.22328
Prompt processing3219.16 tok/s2738.953754.6863
Text generation101.20 tok/s99.80107.4539
Benchmarked· n=328

Aggregated from community-submitted runs, so the spread is wide by nature — it covers different models, resolutions, step counts and settings, not one controlled configuration. Read the middle 50% rather than the median alone. These figures are reproduced with attribution from vladmandic-sd-data-benchmark, which publishes no licence — so we display and link rather than redistribute them.

Questions people ask

What AI models can a Radeon RX 7900 XT run?
1793 of 2118 indexed open-weight models fit a Radeon RX 7900 XT at 131,072 context with q4_0 KV cache, the largest being dolphin-2.6-mixtral-8x7b at I1-IQ2_S. That covers text, vision-language, image, video and speech models.
How much usable memory does a Radeon RX 7900 XT actually have?
Its nameplate is 20 GB, but about 18.60 GiB is available to a model once driver and compositor overhead is accounted for.
Is a Radeon RX 7900 XT fast for local AI?
Its memory bandwidth is 800 GB/s, and that figure — not teraflops — is what governs token generation speed. Capacity decides what you can run; bandwidth decides how fast it runs.