Local AI GPU & VRAM Compatibility Index + Interactive PC & Model Fit Calculator
Every hardware guide in this index separates physical lab benchmarks on our NVIDIA RTX A2000 12GB validation workstation ([Verified Measured]: 26.83s for FLUX.1-schnell Q4_K_S, ~8.0s for FLUX.2 [klein] 4B, ~20.0s for Z-Image-Turbo INT8) from deterministic VRAM headroom math ([Verified Mathematical]: Card_Dedicated_VRAM_GB - (Weight_File_GB + Text_Encoder_Active_GB + VAE_Buffer_GB + OS_Reserve_GB)). We never fabricate render timings for untested GPUs.
1. Interactive PC & Model Fit Calculator
Calculate Exact Dedicated VRAM Headroom on Windows 10/11 & Linux x64
Select your NVIDIA graphics card, diffusion model, operating system, and target resolution to compute deterministic peak VRAM usage before you download weights.
Formula: Dedicated_VRAM (12.0 GB) – [Weights (6.8 GB) + Encoder (1.2 GB) + VAE Buffer (0.9 GB) + OS Reserve (1.5 GB)] = +1.60 GB available headroom.
2. Complete Phase 1 GPU × Model Compatibility Matrix (15 Verified Configurations)
Click any GPU and model pair below to inspect its 12+ hardware attributes, Windows WDDM vs Linux x64 VRAM waterfall, and exact recommended Logen 1.4.0 studio preset:
| NVIDIA GPU | Model Checkpoint | VRAM & Bandwidth | Win Peak Load | Headroom (Full / Offload) | Fit Verdict | Epistemic Tier |
|---|---|---|---|---|---|---|
| NVIDIA RTX A2000 12GB | FLUX.1-schnell (GGUF Q4_K_S) | 12 GB (288 GB/s) | 10.40 GB | +1.60 GB (+2.80 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Measured] |
| NVIDIA RTX A2000 12GB | FLUX.2 [klein] 4B (FP8 / Q8_0) | 12 GB (288 GB/s) | 7.70 GB | +4.30 GB (+5.40 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Measured] |
| NVIDIA RTX A2000 12GB | Z-Image-Turbo 6B (INT8) | 12 GB (288 GB/s) | 9.70 GB | +2.30 GB (+3.40 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Measured] |
| NVIDIA GeForce RTX 3060 12GB | FLUX.1-schnell (GGUF Q4_K_S) | 12 GB (360 GB/s) | 10.40 GB | +1.60 GB (+2.80 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Mathematical] |
| NVIDIA GeForce RTX 3060 12GB | FLUX.2 [klein] 4B (FP8 / Q8_0) | 12 GB (360 GB/s) | 7.70 GB | +4.30 GB (+5.40 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Mathematical] |
| NVIDIA GeForce RTX 3060 12GB | Z-Image-Turbo 6B (INT8) | 12 GB (360 GB/s) | 9.70 GB | +2.30 GB (+3.40 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Mathematical] |
| NVIDIA GeForce RTX 4060 8GB | FLUX.1-schnell (GGUF Q4_K_S) | 8 GB (272 GB/s) | 10.40 GB | -2.40 GB (-1.20 GB offload) | FITS_WITH_SEQUENTIAL_ENCODER_OFFLOAD | [Verified Mathematical] |
| NVIDIA GeForce RTX 4060 8GB | FLUX.2 [klein] 4B (FP8 / Q8_0) | 8 GB (272 GB/s) | 7.70 GB | +0.30 GB (+1.40 GB offload) | FITS_WITH_SEQUENTIAL_ENCODER_OFFLOAD | [Verified Mathematical] |
| NVIDIA GeForce RTX 4060 8GB | Z-Image-Turbo 6B (INT8) | 8 GB (272 GB/s) | 9.70 GB | -1.70 GB (-0.60 GB offload) | FITS_WITH_SEQUENTIAL_ENCODER_OFFLOAD | [Verified Mathematical] |
| NVIDIA GeForce RTX 4070 12GB | FLUX.1-schnell (GGUF Q4_K_S) | 12 GB (504 GB/s) | 10.40 GB | +1.60 GB (+2.80 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Mathematical] |
| NVIDIA GeForce RTX 4070 12GB | FLUX.2 [klein] 4B (FP8 / Q8_0) | 12 GB (504 GB/s) | 7.70 GB | +4.30 GB (+5.40 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Mathematical] |
| NVIDIA GeForce RTX 4070 12GB | Z-Image-Turbo 6B (INT8) | 12 GB (504 GB/s) | 9.70 GB | +2.30 GB (+3.40 GB offload) | FITS_IN_VRAM_COMFORTABLE | [Verified Mathematical] |
| NVIDIA GeForce RTX 3070 8GB | FLUX.1-schnell (GGUF Q4_K_S) | 8 GB (448 GB/s) | 10.40 GB | -2.40 GB (-1.20 GB offload) | FITS_WITH_SEQUENTIAL_ENCODER_OFFLOAD | [Verified Mathematical] |
| NVIDIA GeForce RTX 3070 8GB | FLUX.2 [klein] 4B (FP8 / Q8_0) | 8 GB (448 GB/s) | 7.70 GB | +0.30 GB (+1.40 GB offload) | FITS_WITH_SEQUENTIAL_ENCODER_OFFLOAD | [Verified Mathematical] |
| NVIDIA GeForce RTX 3070 8GB | Z-Image-Turbo 6B (INT8) | 8 GB (448 GB/s) | 9.70 GB | -1.70 GB (-0.60 GB offload) | FITS_WITH_SEQUENTIAL_ENCODER_OFFLOAD | [Verified Mathematical] |
3. Frequently Asked Questions: GPU VRAM Sizing for Local AI
How is local AI VRAM headroom calculated on Windows 10/11 and Linux x64?
We subtract the model weight file size (for example, 6.8 GB for FLUX.1-schnell GGUF Q4_K_S), active text encoder allocation (1.1 to 1.2 GB), 1024×1024 VAE decode buffer (0.8 to 0.9 GB), and OS display reserve (1.5 GB on Windows WDDM or 0.8 GB on Linux x64) from your card’s physical Dedicated VRAM.
Why are exact generation times only listed as Measured on the NVIDIA RTX A2000 12GB?
Under the TitanXT Truth Contract, we only label timings as [Verified Measured] when captured from physical benchmark runs on our hardware (NVIDIA RTX A2000 12GB: 26.83s for FLUX.1-schnell, ~8.0s for FLUX.2 [klein] 4B, ~20.0s for Z-Image-Turbo). Other GPUs use exact mathematical VRAM fit calculations and bandwidth ratio comparisons.
Where can I troubleshoot CUDA out of memory or missing ComfyUI node errors?
Visit our Local AI & ComfyUI Error Troubleshooting Reference for verbatim stack traces, manual CLI fixes, and how Logen 1.4.0 prevents those crashes automatically.