Framework Desktop AMD 395+ (rdna 3.5) cannot run confyui err Fix 2026

This article was originally published on runaihome.com

ComfyUI "No CUDA Cores Available" on AMD RDNA 3.5 GPUs

ComfyUI reports "no CUDA cores available" when launched on AMD RX 395+ (RDNA 3.5) GPUs because ComfyUI defaults to NVIDIA's CUDA backend. AMD GPUs require either the ROCm (ROCm 5.6+ for RDNA 3.5) or DirectML backend. The error occurs when neither backend is properly configured.

Fix 1: Install ROCm-Compatible PyTorch

RDNA 3.5 GPUs require ROCm 5.6 or later with the appropriate PyTorch build.

# Uninstall existing PyTorch
pip uninstall torch torchvision -y

# Install ROCm-compatible PyTorch (verify ROCm 5.6+ installed)
pip install torch torchvision --index-url https://download.pytorch.org/whl/rocm5.6

Verify ROCm detects your GPU:

rocminfo | grep -A 10 "gfx1100"  # RDNA 3.5 uses gfx1100 architecture

Fix 2: Set ComfyUI Launch Environment Variables

Configure ComfyUI to use the AMD backend via environment variables:

# Set device to use HIP (AMD's CUDA equivalent)
export PYTORCH_CUDA_ALLOCATOR=hip
export HIP_VISIBLE_DEVICES=0

# Launch ComfyUI
python main.py --amd

Alternatively, add to your ComfyUI web/index.html or create a launch script:

# Create launch_amd.sh
#!/bin/bash
export HSA_OVERRIDE_GFX_VERSION=11.0.0
export PYTORCH_ENABLE_MPS_FALLBACK=1
python main.py --amd --force-fp16

Fix 3: Use DirectML Backend (Windows)

On Windows, DirectML provides hardware acceleration without ROCm:

# Install DirectML-enabled PyTorch
pip uninstall torch torchvision -y
pip install torch torchvision directml --index-url https://download.pytorch.org/whl/directml

# Launch with DirectML flag
python main.py --directml

Note: DirectML is slower than ROC