AMD · consumer

Radeon RX 6600

Radeon RX 6600 has 8 GB of VRAM at 224 GB/s — about 7.44 GiB usable after driver and compositor overhead. 1416 of 2118 indexed models fit at 8K context with q4_0 KV.

Spec sheet· bandwidth, theoreticalFrom the file· fit from summed bytesPredicted· speed
Memory
8 GB
GDDR6
Bandwidth
224 GB/s
128-bit bus
Tensor FP16
dense
TDP
132 W
$329 MSRP
KV cachef16q8_0q4_0quantizing the KV cache is a ~2× lever on the dominant term at long context
text 1219vision language 103embedding 26audio tts 21video 7image 2audio asr 38

What fits at 8K context

largest quantization that fits, per model · 1416 of 2118 indexed
ModelBest quantParamsWeightsKVTotal in memoryHeadroomtok/s
gemma-4-19B-A4B-it-INSTRUCT-Heretic-UncensoredMoEI1-IQ2_XXS19.0B6.38 GiB0.17 GiB7.44 GiB0.00 GiB22±26.5%
gemma-4-19B-A4B-it-The-DECKARD-Heretic-Uncensored-ThinkingMoEI1-IQ2_XXS19.0B6.38 GiB0.17 GiB7.44 GiB0.00 GiB22±26.5%
gemma-4-19b-a4b-it-REAP-hereticMoEI1-IQ2_XXS19.0B6.38 GiB0.17 GiB7.44 GiB0.00 GiB22±26.5%
Gemma-4-19BMoEI1-IQ2_XXS19.0B6.38 GiB0.17 GiB7.44 GiB0.00 GiB22±26.5%
GPT-NeoX-20B-ErebusI1-IQ1_S20.6B4.12 GiB2.32 GiB7.44 GiB0.00 GiB22±26.5%
codegeex4-all-9bIQ4_NL9.4B5.08 GiB1.41 GiB7.44 GiB0.00 GiB22±26.5%
Apriel-1.6-15b-ThinkerI1-IQ3_S14.9B6.06 GiB0.42 GiB7.43 GiB0.01 GiB22±26.5%
Phi-3-medium-128k-instructIQ3_M14.0B6.03 GiB0.44 GiB7.43 GiB0.01 GiB22±26.5%
Phi-3-medium-4k-instructI1-IQ3_M14.0B6.03 GiB0.44 GiB7.43 GiB0.01 GiB22±26.5%
granite-vision-4.1-4bBF164.0B6.34 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
Parable-Granite-4.1-3B-Claude-Fable-5F163.4B6.34 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
granite-4.0-microBF163.4B6.34 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
granite-4.1-3bBF163.4B6.34 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
granite-4.0-micro-baseBF163.4B6.34 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
dolphincoder-starcoder2-15bKV unresolvedI1-IQ3_XS16.0B6.25 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
starcoder2-15bKV unresolvedIQ3_XS16.0B6.25 GiB0.18 GiB7.42 GiB0.02 GiB22±26.5%
Qwen2.5-3B-Instruct-abliteratedQ8_03.1B6.43 GiB0.08 GiB7.42 GiB0.02 GiB22±26.5%
GLM-4.7-Flash-DerestrictedMoEI1-IQ1_M31.2B6.39 GiB0.12 GiB7.42 GiB0.02 GiB83±37%
Huihui-GLM-4.7-Flash-abliteratedMoEI1-IQ1_M31.2B6.39 GiB0.12 GiB7.42 GiB0.02 GiB83±37%
Wan2.1-T2V-1.3BQ4_01.4B6.50 GiB0.00 GiB7.42 GiB0.02 GiB22±26.5%
reka-flash-3.1I1-IQ1_S20.9B6.15 GiB0.29 GiB7.42 GiB0.02 GiB22±26.5%
granite-8b-code-instruct-4kI1-Q6_K8.1B6.16 GiB0.32 GiB7.41 GiB0.03 GiB22±26.5%
granite-8b-code-base-4kI1-Q6_K8.1B6.16 GiB0.32 GiB7.41 GiB0.03 GiB22±26.5%
Grug-12BQ3_K_L12.0B6.20 GiB0.27 GiB7.41 GiB0.03 GiB22±26.5%
gemma-4-12B-it-Esper4Q3_K_L12.0B6.20 GiB0.27 GiB7.41 GiB0.03 GiB22±26.5%
gemma-4-12B-itQ3_K_L12.0B6.20 GiB0.27 GiB7.41 GiB0.03 GiB22±26.5%
internlm2-math-plus-20bI1-IQ2_S19.9B6.03 GiB0.42 GiB7.41 GiB0.03 GiB22±26.5%
Forsaken-Void-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Silver-Siren-ST-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Tess-3-Mistral-Nemo-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
MN-12B-Runeweaver-RP-RUI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Dans-PersonalityEngine-V1.3.0-12bI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Impish_Bloodmoon_12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Wayfarer-2-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Wayfarer-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Muse-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Vikhr-Nemo-12B-Instruct-R-21-09-24Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-Base-2407Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
writing-roleplay-20k-context-nemo-12b-v1.0Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
mini-magnum-12b-v1.1Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Lumimaid-v0.2-12BQ3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
MN-Violet-Lotus-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Rocinante-X-12B-v1-Heretic-UncensoredI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Heretica-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Violet_Twilight-v0.2Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Lumimaid-Magnum-v4-12BQ3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
arcee-fusion-lumaid-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-NeMo-12B-AbliteratedI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Captain-Eris_Violet-V0.420-12BI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Rocinante-X-12B-v1-absolute-heresyI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Rocinante-X-12B-v1I1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-Gutenberg-Doppel-12BQ3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-Instruct-2407Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
magnum-v4-12bQ3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
MN-12b-RP-InkQ3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-12B-ArliAI-RPMax-v1.1Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-2407-12B-Thinking-Claude-Gemini-GPT5.2-Uncensored-HERETICI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Dans-SakuraKaze-V1.0.0-12bI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-Inst-2407-12B-Thinking-Uncensored-HERETIC-HI-Claude-OpusI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±26.5%
Mistral-Nemo-Instruct-2407-12B-Thinking-M-Claude-Opus-High-ReasoningI1-Q3_K_L12.2B6.11 GiB0.35 GiB7.41 GiB0.03 GiB22±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 generation2.06 it/s0.903.3091
Benchmarked· n=91

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 6600 run?
1416 of 2118 indexed open-weight models fit a Radeon RX 6600 at 8,192 context with q4_0 KV cache, the largest being gemma-4-19B-A4B-it-INSTRUCT-Heretic-Uncensored at I1-IQ2_XXS. That covers text, vision-language, image, video and speech models.
How much usable memory does a Radeon RX 6600 actually have?
Its nameplate is 8 GB, but about 7.44 GiB is available to a model once driver and compositor overhead is accounted for.
Is a Radeon RX 6600 fast for local AI?
Its memory bandwidth is 224 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.