Can the RTX 4090 Laptop 16 GB run SDXL 1.0?
Yes. 16-bit fits on the RTX 4090 Laptop 16 GB with 8.9 GB to spare.
16-bit (6.9 GB) needs about 7.1 GB in use, so 8.9 GB of the 16 GB stays free: room for a larger image, a LoRA or a ControlNet.
01What to download
| Part | File | Folder | Size | |
|---|---|---|---|---|
| Checkpoint | sd_xl_base_1.0.safetensors 16-bit · stabilityai/stable-diffusion-xl-base-1.0 | models/checkpoints | 6.9 GB | Download → |
| Total download · keep about the same free on disk | 6.9 GB | |||
One file: the checkpoint already contains the text encoders and the VAE. Sizes from Hugging Face, 2026-10-01.
02Every SDXL file on 16 GB
| File | Size | Needed | On this card | Quality | Download |
|---|---|---|---|---|---|
| 16-bit ← SAFETENSORS · stabilityai | 6.9 GB | 7.1 GB | fits · 8.9 GB spare | the original weights | Hugging Face → |
“Needed” adds 1.2 GB of working memory for SDXL and a 0.8 GB reserve. Sizes 2026-10-01. The 6.94 GB checkpoint also holds the two text encoders and the VAE. During sampling only the UNet (about 5.1 GB at 16-bit, 2.6B parameters) has to sit in VRAM, so that is the figure used for the 16-bit file.
03The text encoder
The text encoder is inside the checkpoint, so there is nothing extra to download.
04Measured and reported results
Nobody has sent measured numbers for this pair yet. If you run SDXL on a RTX 4090 Laptop 16 GB, send your time per image and peak VRAM and it will appear here, credited.
05About the RTX 4090 Laptop 16 GB
The RTX 4090 Laptop 16 GB is an Ada Lovelace GPU with hardware FP8, so ComfyUI can compute Comfy-Org's FP8 files natively: small and fast. (Plain FP8 files use FP8 maths with the --fast fp8_matrix_mult option.) As a laptop GPU it runs at a lower power limit than desktop cards (80–150 W depending on the laptop). The memory verdicts are the same; speed depends heavily on how much power the laptop maker allows.
16 GB GDDR6 · 256-bit · Ada Lovelace · 80–150 W. Everything that runs on it →
06Questions
How much VRAM does SDXL need?
Around 7.1 GB with the smallest file (16-bit).
Which SDXL file should I download for the RTX 4090 Laptop 16 GB?
16-bit (6.9 GB) from stabilityai/stable-diffusion-xl-base-1.0.
How much do I need to download for SDXL on the RTX 4090 Laptop 16 GB?
6.9 GB: sd_xl_base_1.0.safetensors.