RADV Driver Guide for BC-250¶

This guide covers the Radeon Vulkan (RADV) driver, which is the primary graphics driver for BC-250 on Linux.

What is RADV?¶

RADV (Radeon Vulkan) is the open-source Vulkan driver for AMD GPUs, developed as part of Mesa. It provides Vulkan API support for the BC-250's "Cyan Skillfish" GPU (GFX1013 architecture).

Why RADV for BC-250?¶

The BC-250 only works on Linux for gaming and desktop use. There is no Windows GPU driver support, making RADV your only option for graphics acceleration:

Linux-only GPU support - No Windows drivers exist
Open-source - Part of Mesa, actively maintained
BC-250 specific support - Added in Mesa 25.1.0
Better than alternatives - AMDVLK and proprietary drivers don't support this GPU
Vulkan + Zink - Handles both Vulkan games and OpenGL (via Zink translation)

BC-250 GPU Architecture¶

Codename: Cyan Skillfish
Architecture: GFX1013 (RDNA 1.5)
Compute Units: 24 RDNA2 CUs
Features: Hardware ray tracing cores
VRAM: 512MB-15.5GB configurable (shared with CPU)
Vulkan ID: RADV GFX1013

RDNA 1.5 Hybrid

The BC-250 uses a unique hybrid architecture combining Zen 2 CPU cores with cut-down PS5 GPU cores. It's not a standard AMD APU - it uses GDDR6 instead of DDR4/DDR5, and has hardware features not found in consumer APUs.

Mesa Version Requirements¶

Minimum: Mesa 25.1.0¶

BC-250 support was added upstream in Mesa 25.1.0. Do not use older versions - they will not work properly or at all.

Recommended: Mesa 25.1.3+¶

For stability and performance, use Mesa 25.1.3 or newer:

25.1.0 - Initial BC-250 support
25.1.3 - Improved stability
25.1.5+ - Best tested version, recommended

What Changed in Mesa 25.1?¶

Mesa 25.1 includes critical fixes for BC-250:

Compute queue fix - Disables broken compute-only queue (MR 33116)
Unified heap on APU - Memory management improvements
GFX1013 recognition - Proper GPU identification
Artifact fixes - Reduces visual glitches

Mesa 25.0 and Older

Mesa versions before 25.1 require custom patches and are no longer supported. All major distributions now have Mesa 25.1+ in their repositories.

Installation by Distribution¶

Fedora 42/43¶

Mesa 25.1 is now in mainline Fedora repositories (as of Fedora 43):

# Update to latest Mesa
sudo dnf update mesa-*

# Verify version
glxinfo | grep "OpenGL version"
# Should show: Mesa 25.1.X or newer

Fedora 42 may need a manual update if on an older installation:

# Check current version
dnf list installed | grep mesa

# If < 25.1, update system
sudo dnf upgrade --refresh

Bazzite¶

Bazzite includes Mesa 25.1+ by default:

# Check Mesa version
rpm -qa | grep mesa

# Update if needed
rpm-ostree upgrade

# For flatpak apps, install mesa-git (see Flatpak section below)

Arch Linux / CachyOS¶

Mesa 25.1+ is in the official Arch repositories:

# Install/update Mesa
sudo pacman -S mesa vulkan-radeon lib32-vulkan-radeon

# Verify installation
pacman -Q mesa vulkan-radeon

CachyOS uses the same packages but may have additional optimizations:

# CachyOS may have mesa-git available
sudo pacman -S mesa-git vulkan-radeon-git

Debian / PikaOS¶

Debian requires the experimental repository for Mesa 25.1:

# Add experimental repo to /etc/apt/sources.list
deb http://deb.debian.org/debian experimental main contrib non-free

# Install Mesa from experimental
sudo apt update
sudo apt install -t experimental mesa-vulkan-drivers libgl1-mesa-dri mesa-utils

# Verify
glxinfo | grep "OpenGL version"

PikaOS includes Mesa 25.1+ out of the box:

# Update system
sudo apt update && sudo apt upgrade

# Mesa 25.1 should be installed by default

Manjaro¶

Manjaro repositories include Mesa 25.1+:

# Update Mesa
sudo pacman -Syu mesa

# Install Vulkan drivers
sudo pacman -S vulkan-radeon lib32-vulkan-radeon

Verification Commands¶

Check Mesa Version¶

# OpenGL version string includes Mesa version
glxinfo | grep "OpenGL version"
# Expected: OpenGL version string: 4.6 (Compatibility Profile) Mesa 25.1.X

# Alternative method
vulkaninfo | grep "driverVersion"

Check RADV is Active¶

# Should show RADV, not AMDVLK or llvmpipe
vulkaninfo | grep "driverName"
# Expected: driverName = radv

# Check GPU name
vulkaninfo | grep "deviceName"
# Expected: deviceName = AMD Radeon Graphics (RADV GFX1013)

Check Vulkan Capabilities¶

# Full Vulkan device info
vulkaninfo | grep -A 20 "VkPhysicalDeviceProperties"

# Should show:
# - deviceType = PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU
# - vendorID = 0x1002 (AMD)
# - driverName = radv

Verify GPU is Not Using Software Rendering¶

# Check for llvmpipe (software rendering)
vulkaninfo | grep -i llvmpipe
# Should return NOTHING - if llvmpipe appears, GPU is not working

# Alternative check
glxinfo | grep "OpenGL renderer"
# Should show: AMD Radeon Graphics (gfx1013, LLVM...)
# NOT: llvmpipe or software rasterizer

Performance Tuning¶

Environment Variables¶

These environment variables control RADV behavior and can fix issues or improve performance.

Core RADV Variables¶

# Force RADV (not AMDVLK) - usually automatic
export AMD_VULKAN_ICD=RADV

# Disable compute queue (may not be needed on Mesa 25.1+)
# Only use if you have visual artifacts
export RADV_DEBUG=nocompute

# Disable hierarchical Z buffer (fixes some visual glitches)
export RADV_DEBUG=nohiz

# Combine multiple debug flags
export RADV_DEBUG=nocompute,nohiz

RADV_DEBUG=nocompute on Mesa 25.1+

Mesa 25.1 includes MR 33116 which automatically disables the broken compute-only queue. You may not need RADV_DEBUG=nocompute anymore, but it doesn't hurt to keep it.

Memory Management¶

# Enable unified heap on APU (recommended)
# Add to /etc/drirc:
<driconf>
    <device>
        <application name="Default">
            <option name="radv_enable_unified_heap_on_apu" value="true" />
        </application>
    </device>
</driconf>

This configuration improves memory management for the BC-250's shared CPU/GPU memory architecture.

OpenGL via Zink¶

For OpenGL applications, use Zink (OpenGL on Vulkan) for better performance:

# Force Zink for OpenGL
export MESA_LOADER_DRIVER_OVERRIDE=zink

# Or per-application
MESA_LOADER_DRIVER_OVERRIDE=zink ./opengl_game

Steam Launch Options¶

Set environment variables per-game in Steam:

# Right-click game -> Properties -> Launch Options

# Basic (recommended)
RADV_DEBUG=nohiz %command%

# With compute queue disabled
RADV_DEBUG=nocompute,nohiz %command%

# With Zink for OpenGL games
MESA_LOADER_DRIVER_OVERRIDE=zink %command%

# All combined
AMD_VULKAN_ICD=RADV RADV_DEBUG=nohiz %command%

System-Wide Configuration¶

For system-wide settings, add to /etc/environment:

# Edit /etc/environment
sudo nano /etc/environment

# Add these lines:
AMD_VULKAN_ICD=RADV
RADV_DEBUG=nohiz
MESA_LOADER_DRIVER_OVERRIDE=zink

Apply changes:

# Log out and back in, or reboot
sudo reboot

Vulkan ICD Configuration¶

Make sure RADV ICD files are used by Vulkan loader:

# Check ICD files exist
ls /usr/share/vulkan/icd.d/
# Should show: radeon_icd.x86_64.json, radeon_icd.i686.json

# If needed, manually set ICD files
export VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/radeon_icd.x86_64.json:/usr/share/vulkan/icd.d/radeon_icd.i686.json

This is rarely needed on modern distributions but may help with hardware acceleration in Steam Big Picture mode.

Known Issues with RADV on BC-250¶

Visual Artifacts and Glitches¶

Symptoms: - Texture corruption - Flickering - Visual glitches in games - Black textures

Solutions:

Update to Mesa 25.1.3+ - Many artifacts fixed in newer versions
Use RADV_DEBUG=nohiz - Disables hierarchical Z buffer
Apply MR 33962 - Additional artifact fixes (may need to compile Mesa yourself)
Enable unified heap - Add drirc configuration (see Memory Management section)

# Test with nohiz first
RADV_DEBUG=nohiz ./game

# If that doesn't help, try nocompute as well
RADV_DEBUG=nocompute,nohiz ./game

Compute Queue Issues¶

Symptoms: - Games crash on launch - Applications hang when using compute shaders - "Out of memory" errors despite available VRAM

Solution:

The compute-only queue on BC-250 is broken. Mesa 25.1+ disables it automatically, but you can force it:

export RADV_DEBUG=nocompute

Background: The BC-250's compute queue has hardware issues. Mesa 25.1 includes a workaround that detects GFX1013 and disables the compute-only queue by default.

Limited VRAM Visibility in Vulkan¶

Symptoms: - Vulkan sees only ~10GB of 12GB VRAM split - Applications report less memory than configured in BIOS

Explanation:

This is a known limitation with Vulkan on BC-250. ROCm can see the full VRAM, but RADV may report less:

BIOS configured: 4GB CPU / 12GB GPU
Vulkan reports: ~10GB available
ROCm reports: Full 12GB

Workaround:

Increase TTM memory limits to expose more system memory to GPU:

# Add to /etc/modprobe.d/ttm-mem-limit.conf
options ttm pages_limit=3959290 page_pool_size=3959290

# Rebuild initramfs
sudo dracut --regenerate-all --force  # Fedora
sudo mkinitcpio -P                     # Arch
sudo update-initramfs -u               # Debian/Ubuntu

# Reboot

This allows the GPU to use system RAM as VRAM overflow, partially compensating for the limited visibility.

No Video Encoding/Decoding Hardware Acceleration¶

Symptoms: - VA-API doesn't work - vainfo shows errors or no devices - Hardware video encoding fails

Explanation:

The BC-250's video encode/decode hardware (VCN) is disabled or non-functional. This is a hardware limitation, not a driver issue:

# vainfo will fail
vainfo
# Error: vaInitialize failed with error code -1 (unknown libva error)

Workaround:

Use software encoding/decoding (CPU). Performance is acceptable for most use cases:

# For video playback, use software decoding
# mpv, VLC, etc. will fall back automatically

# For OBS recording, use software encoder (x264)

Ray Tracing Performance¶

Symptoms: - Ray traced games run slowly - RT cores not being utilized effectively

Explanation:

The BC-250 has hardware RT cores, but they're RDNA 1.5 generation (not as efficient as RDNA ⅔). Mesa's RT implementation is improving but not fully optimized for GFX1013:

Portal RTX: ~40 FPS at 720p (with RT)
Quake 2 RTX: Playable but slow
Modern RT games: Generally too demanding

Recommendations: - Disable ray tracing in demanding games - Use lower resolutions (720p-900p) for RT games - Wait for Mesa improvements

Comparison with Other AMD Drivers¶

RADV vs AMDVLK¶

Feature	RADV	AMDVLK
Open Source	Yes (Mesa)	Yes (AMD)
BC-250 Support	✅ Yes (Mesa 25.1+)	❌ No
Performance	Better for most games	Good for some specific games
Updates	Frequent (Mesa releases)	Less frequent
Compatibility	Excellent	Limited for BC-250

Verdict: RADV is the only choice for BC-250. AMDVLK does not support GFX1013.

RADV vs Proprietary AMD Drivers¶

Feature	RADV	AMD PRO
BC-250 Support	✅ Yes	❌ No
Gaming	Excellent	Not applicable
OpenGL	Via Zink	Native
Vulkan	Native	Native
Linux Kernel	Upstream AMDGPU	Same (amdgpu)

Verdict: AMD's proprietary driver (AMDGPU-PRO) does not support BC-250. Even the open-source amdgpu kernel module + proprietary userspace won't work. RADV is required.

RADV vs ROCm¶

Feature	RADV	ROCm
Purpose	Gaming (Vulkan)	Compute (HIP/OpenCL)
BC-250 Support	✅ Full	⚠️ Partial
Graphics	Excellent	No
Compute	Limited (Vulkan compute)	Full (when working)
AI/ML	Via Vulkan backends	Native

Verdict: Use RADV for gaming, ROCm for compute workloads (if you can get it working - see LLM inference section).

ROCm on BC-250 is Experimental

ROCm support for GFX1013 is incomplete. rocBLAS is missing pre-compiled kernels for this architecture, requiring manual compilation or workarounds. For most users, stick with RADV + Vulkan compute backends (e.g., for llama.cpp).

Advanced Topics¶

Mesa Compilation from Source¶

If you need bleeding-edge fixes or custom patches:

Install Build Dependencies¶

Fedora:

sudo dnf install meson ninja-build gcc g++ python3-mako \
    libdrm-devel libxcb-devel libX11-devel libxshmfence-devel \
    libXext-devel libXfixes-devel libXrandr-devel \
    wayland-protocols-devel wayland-devel \
    elfutils-devel llvm-devel cmake flex bison

Arch:

sudo pacman -S meson ninja gcc python-mako libdrm libxcb libx11 \
    libxshmfence libxext libxfixes libxrandr \
    wayland wayland-protocols elfutils llvm cmake flex bison

Compile Mesa¶

# Clone Mesa
git clone https://gitlab.freedesktop.org/mesa/mesa.git
cd mesa

# Checkout stable branch or apply custom patches
git checkout mesa-25.1

# Apply custom patches if needed
# git am /path/to/patch.patch

# Configure build
meson setup builddir/ \
    -Dprefix=/usr/local \
    -Dvulkan-drivers=amd \
    -Dgallium-drivers=radeonsi,zink \
    -Dplatforms=x11,wayland \
    -Dbuildtype=release

# Compile (use all CPU cores)
meson compile -C builddir/

# Install
sudo meson install -C builddir/

# Verify
glxinfo | grep "OpenGL version"
vulkaninfo | grep "driverName"

Compiling Mesa Can Break Your System

Installing Mesa to /usr/local may conflict with system packages. Only do this if you know how to revert changes. Consider using a separate prefix like /opt/mesa-git and setting LD_LIBRARY_PATH.

Applying BC-250 Specific Patches¶

Some community patches may not be upstream yet:

# Example: Apply MR 33962 (artifact fixes)
cd mesa
git fetch origin merge-requests/33962/head:mr33962
git checkout mr33962

# Compile as above

Using Flatpak Apps with Mesa-git¶

Flatpak apps use their own runtime Mesa, which may be outdated. Force them to use newer Mesa:

# Add Flathub Beta repository
flatpak remote-add --if-not-exists flathub-beta \
    https://flathub.org/beta-repo/flathub-beta.flatpakrepo

# Install mesa-git for runtime 24.08 (check your flatpak runtime version)
flatpak install --system flathub-beta org.freedesktop.Platform.GL.mesa-git//24.08
flatpak install --system flathub-beta org.freedesktop.Platform.GL32.mesa-git//24.08

# Configure systemd to use mesa-git
sudo mkdir -p /etc/systemd/system/service.d
sudo bash -c 'echo -e "[Service]\nEnvironment=FLATPAK_GL_DRIVERS=mesa-git" > \
    /etc/systemd/system/service.d/99-flatpak-mesa-git.conf'

# Reboot or restart flatpak services
sudo systemctl daemon-reload

Verify:

# Run flatpak app and check Mesa version
flatpak run --command=sh com.valvesoftware.Steam
$ glxinfo | grep "OpenGL version"

Flatpak Runtime Version

Runtimes older than 23.08 may not support Mesa 25.1. Ensure your flatpak apps use runtime 24.08 or newer.

LLM Inference with Vulkan¶

For running large language models (LLMs) using Vulkan backend:

llama.cpp with Vulkan:

# Download pre-compiled llama.cpp Vulkan binary
wget https://github.com/ggerganov/llama.cpp/releases/download/b6104/llama-b6104-bin-ubuntu-vulkan-x64.zip
unzip llama-b6104-bin-ubuntu-vulkan-x64.zip
cd build/bin

# Set environment variable to avoid OOM errors
export GGML_VK_FORCE_MAX_ALLOCATION_SIZE=2000000000  # 2GB chunks

# Run inference
./llama-server --model /path/to/model.gguf --gpu-layers 99

# Expected output:
# ggml_vulkan: Found 1 Vulkan devices:
# ggml_vulkan: 0 = AMD Radeon Graphics (RADV GFX1013) (radv) | uma: 1 | fp16: 1

Performance: - 4-bit quantized 8B model: ~60 tokens/sec - 12GB VRAM split recommended for larger models - Vulkan backend more stable than ROCm for BC-250

Known Issues: - Vulkan sees ~10GB of 12GB VRAM (see VRAM visibility issue above) - Large models (70B+) may OOM even with quantization - Use GGML_VK_FORCE_MAX_ALLOCATION_SIZE to prevent allocation errors

Troubleshooting¶

RADV Not Being Used (llvmpipe fallback)¶

Symptoms:

vulkaninfo | grep deviceName
# Shows: llvmpipe (LLVM 18.1.0, 256 bits)

Cause: Mesa drivers not installed or not working.

Solution: 1. Verify Mesa version: glxinfo | grep Mesa 2. Install Vulkan RADV driver: sudo dnf install mesa-vulkan-drivers (Fedora) or equivalent 3. Check amdgpu kernel module: lsmod | grep amdgpu 4. Check dmesg for errors: dmesg | grep -i amdgpu

Vulkan Initialization Fails¶

Symptoms:

vulkaninfo
# Failed to create Vulkan instance
# ERROR: [Loader Message] Code 0 : No drivers found

Cause: ICD files missing or incorrect.

Solution:

# Check ICD files
ls /usr/share/vulkan/icd.d/
# Should have: radeon_icd.x86_64.json

# Manually set ICD path
export VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/radeon_icd.x86_64.json

# Reinstall Mesa Vulkan drivers
sudo dnf reinstall mesa-vulkan-drivers  # Fedora
sudo pacman -S vulkan-radeon            # Arch

Visual Artifacts Persist After Mesa 25.1¶

Symptoms: - Textures still corrupted - Flickering in certain games - Black squares/triangles

Solution (priority order):

Update to Mesa 25.1.5+
Use RADV_DEBUG=nohiz
Apply MR 33962 patch (requires compiling Mesa)
Enable unified heap in drirc (see Memory Management section)
Test with different kernel versions (6.12-6.14 work best)

Games Crash on Shader Compilation¶

Symptoms: - Game crashes during loading - "Compiling shaders" freezes - Steam shader pre-caching fails

Solution:

# Clear shader cache
rm -rf ~/.cache/mesa_shader_cache
rm -rf ~/.local/share/Steam/steamapps/shadercache

# Disable shader cache temporarily
export MESA_SHADER_CACHE_DISABLE=1

# Run game
./game

# If that works, re-enable cache and pre-compile:
unset MESA_SHADER_CACHE_DISABLE
# Let game rebuild cache

Poor Performance Despite RADV Working¶

Symptoms: - Low FPS in games - GPU usage low in nvtop - GPU frequency stuck at 1500MHz

Cause: GPU governor not running (see System Configuration guide).

Quick Check:

# Check GPU frequency
cat /sys/class/drm/card0/device/pp_dpm_sclk

# Should show multiple frequency levels with * at current:
# 0: 1000Mhz
# 1: 1500Mhz *
# 2: 2000Mhz

# If stuck at 1500MHz, governor is not working
systemctl status oberon-governor

Solution: Install and configure GPU governor (see System Configuration guide).

Summary¶

RADV is the only working graphics driver for BC-250 on Linux:

✅ Required: Mesa 25.1.0 minimum (25.1.5+ recommended)
✅ Works with: All major Linux distributions (Fedora, Arch, Debian, Bazzite, etc.)
✅ Performance: Good for 720p-1080p gaming, competitive with RX 6600
✅ Environment variables: RADV_DEBUG=nohiz recommended, nocompute may not be needed on Mesa 25.1+
✅ Known issues: Visual artifacts (mostly fixed), limited VRAM visibility, no VA-API
❌ No Windows support: BC-250 GPU does not work on Windows

For most users, install Mesa 25.1+ from your distribution's repositories, set RADV_DEBUG=nohiz in Steam launch options, install the GPU governor, and enjoy gaming.

Last Updated: 2025-11-21 Based on: Discord community discussions (7,000+ messages analyzed) See Also: Linux Setup Guide, System Configuration, Gaming & Performance