Can the RTX 3060 Laptop 6 GB run Stable Diffusion 3.5 Large?
Nothing fits entirely, but Q4_1 (5.3 GB) overflows by only about 1.6 GB. ComfyUI keeps that part in system RAM automatically: slower than a full fit, but usable.
01What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Model | sd3.5_large-Q4_1.gguf Q4_1 · city96/stable-diffusion-3.5-large-gguf | models/unet | 5.3 GB | Download → |
| Text encoder | t5xxl_fp8_e4m3fn.safetensors T5-XXL FP8 · Comfy-Org/stable-diffusion-3.5-fp8 | models/text_encoders | 4.9 GB | Download → |
| Text encoder | clip_l.safetensors CLIP-L · Comfy-Org/stable-diffusion-3.5-fp8 | models/text_encoders | 0.2 GB | Download → |
| Text encoder | clip_g.safetensors CLIP-G · Comfy-Org/stable-diffusion-3.5-fp8 | models/text_encoders | 1.4 GB | Download → |
| Total download · keep about the same free on disk | 11.8 GB | |||
Alternatives: T5-XXL FP16 (9.8 GB). The 16-bit text encoder is a little more faithful; the smaller one is chosen here because it loads faster and needs less RAM. Sizes read from Hugging Face (2026-09-25). “Download” links start the file directly; the file name links are the same files the official ComfyUI workflows use.
System RAM: 32 GB or more. ComfyUI keeps the model file, the text encoder and the VAE in system RAM and moves them to the GPU as needed. With this set of files that is about 11.8 GB, plus roughly 6 GB for Windows, ComfyUI and a browser: 17.8 GB in total. With less RAM it still runs, but Windows starts swapping to disk and loading gets very slow. calculated
02Every SD 3.5 Large file on 6 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit SAFETENSORS · stabilityai | 16.5 GB | 18.8 GB | 12.8 GB too big | the original weights | Hugging Face → |
| Q8_0 GGUF · city96 | 8.8 GB | 11.1 GB | 5.1 GB too big | practically identical to the original | Hugging Face → |
| Q5_1 GGUF · city96 | 6.3 GB | 8.6 GB | 2.6 GB too big | close; small differences in fine detail | Hugging Face → |
| Q4_1 ← GGUF · city96 | 5.3 GB | 7.6 GB | spills 1.6 GB | good; some loss in fine detail and text | Hugging Face → |
Sizes from the Hugging Face file listing, read 2026-09-25. “Needed” = file + 1.5 GB working memory for this model + 0.8 GB kept free for the system.
03The text encoder
CLIP-L + CLIP-G + T5-XXL: 9.8 GB as 16-bit, 4.9 GB as FP8 (T5-XXL sizes shown; CLIP-L and CLIP-G add about 1.6 GB). ComfyUI encodes the prompt first and can push the encoder out of VRAM before sampling, so it does not have to fit together with the model. On 6 GB the FP8 encoder fits on its own, so prompt encoding stays fast.
04About this GPU
The RTX 3060 Laptop 6 GB (Ampere) has no FP8 compute. FP8 files still load and save memory, but ComfyUI converts them back before the maths, so there is no speed gain — Q8_0 GGUF is the closer-to-original 8-bit choice. ComfyUI can compute INT8 files natively on NVIDIA, which is worth a try where a model offers one. As a laptop GPU it runs at a lower power limit than desktop cards (60–115 W depending on the laptop). The memory verdicts are the same; speed depends heavily on how much power the laptop maker allows.
RTX 3060 Laptop 6 GB: 6 GB GDDR6 · 192-bit · Ampere · 60–115 W. Everything that runs on the RTX 3060 Laptop 6 GB →
05What more VRAM would change
With 12 GB you could run SD 3.5 Large at 8-bit or better (Q8_0, 8.8 GB) with no offloading: for example on the RTX 5070 12 GB, RTX 4070 Super 12 GB, RTX 4070 12 GB.
What changes from the RTX 3060 Laptop 6 GB to the RTX 5060 Ti 16 GB →
06Measured and reported results
Nobody has sent measured numbers for this pair yet. If you run SD 3.5 Large on a RTX 3060 Laptop 6 GB, send your time per image and peak VRAM and it will appear here, credited.
07Questions
How much VRAM does SD 3.5 Large need?
Around 7.6 GB with the smallest file (Q4_1) and 11.1 GB with an 8-bit file (Q8_0), counting working memory and a small system reserve. The full 16-bit file needs about 18.8 GB.
Which SD 3.5 Large file should I download for the RTX 3060 Laptop 6 GB?
Q4_1 (5.3 GB) from city96/stable-diffusion-3.5-large-gguf. Load it with Unet Loader (GGUF) from the ComfyUI-GGUF node pack.
Is FP8 faster than GGUF on the RTX 3060 Laptop 6 GB?
No. This GPU has no FP8 compute, so ComfyUI converts FP8 weights back before the maths. FP8 only saves memory here; Q8_0 GGUF is the closer-to-original 8-bit pick.
How much do I need to download for SD 3.5 Large on the RTX 3060 Laptop 6 GB?
About 11.8 GB for the model file, text encoder and VAE listed on this page, and the same again free on disk. With a 6 GB card, 32 GB of system RAM or more is recommended.