amd-bc250-docs/docs/reference/quick-reference.md

Quick Reference Guide

Fast answers to common questions. For detailed information, see the full documentation pages.

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Quick Start Checklist

Hardware Setup

• BC-250 board
• 300W+ 12V PSU with PCIe 8-pin
• High static pressure 120mm fan (Arctic P12/P14)
• DisplayPort cable or passive DP-HDMI adapter
• USB stick (FAT32) for BIOS flash
• M.2 NVMe SSD (optional but recommended)
• USB WiFi adapter (board has no wireless)

Software Setup

1. Flash BIOS - Get modded BIOS from GitLab
2. Set VRAM to 512MB in BIOS after flashing
3. Clear CMOS (critical after USB flash)
4. Install Fedora/Bazzite with "Basic Graphics Mode"
5. Run setup script to install Mesa 25.1+ and governor
6. Remove nomodeset from GRUB after drivers installed
7. Test a game!

Full quick start guide →

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Critical Settings

BIOS Configuration

Setting	Value	Why
UMA Frame Buffer Size	512MB	Dynamic VRAM allocation
IOMMU	MUST be Disabled	IOMMU is broken - causes display failures and crashes
Fan Control	Customize	Stock is too aggressive or too quiet

BIOS guide →

Kernel Requirements

• Use: Kernel 6.18.18 LTS (recommended), 6.17.11+, or 6.12.x-6.14.x LTS (stable)
• Avoid: Kernel 6.15.0-6.15.6, 6.17.8-6.17.10 (GPU fails), and 6.19.x (PCIe issues on BC-250)
• Boot parameter: nomodeset during install, remove after drivers installed

Kernel Parameters

# Required in /etc/default/grub GRUB_CMDLINE_LINUX_DEFAULT:
quiet

# Optional performance boost:
mitigations=off

# For older kernels <6.10 only:
amdgpu.sg_display=0

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Power & Cooling

Power Draw

State	Consumption
Idle	50-80W
Light gaming	100-150W
Heavy gaming	150-200W
Maximum (RT)	Up to 235W

Temperature Targets

State	Temperature	Status
Idle	40-60°C	✅ Good
Gaming	70-85°C	✅ Good
Stress	85-90°C	⚠️ Caution
Critical	>90°C	❌ Too hot

Recommended Fans

1. Arctic P12 Max - 6.9 mmH2O, best value
2. Noctua NF-A12x25 - Quieter, premium
3. Arctic P14 Max - 140mm option

!!!warning "High Static Pressure Required" You NEED fans with 3+ mmH2O static pressure. Regular case fans won't work.

Cooling guide →

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Software Requirements

Operating System

Recommended:

• Fedora 43 Workstation (easiest)
• Bazzite (best for gaming)
• CachyOS (best performance, harder setup)

Also works:

• Manjaro, Arch, Debian (with effort)

Doesn't work:

• Windows (no GPU drivers)

Note: SteamOS now works after Mesa updates

Driver Versions

Component	Minimum	Recommended
Mesa	25.1.0	25.2.4+
Kernel	6.12.x	6.18.18 LTS or 6.17.11+
Governor	Any	cyan-skillfish-governor-tt or -smu

Linux setup guide →

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VRAM Configuration

512MB Dynamic (Recommended)

• Automatically allocates between CPU/GPU
• ~10-15GB CPU RAM, up to 12GB VRAM when needed
• Best for most users

Fixed Allocations

• 10GB/6GB - Best for AAA gaming, fixes ZRAM conflicts
• 8GB/8GB - Balanced, good for AI/compute
• 12GB/4GB - Light gaming, maximum system RAM

!!!info "ZRAM Conflict" If RDR2 or Company of Heroes 3 crashes, switch from 512MB dynamic to 10GB/6GB fixed.

VRAM guide →

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Display Connection

Working Solutions

Method	Resolution	Audio	Notes
Native DP	Up to 4K60	✅	Best option
Passive DP-HDMI	Up to 1440p60	✅	Most common
Active DP-HDMI	4K60+	❌	Video only, no audio
USB DAC	N/A	✅	Workaround for audio

!!!danger "Active Adapters Break Audio" Active (powered) DP-to-HDMI adapters don't pass audio properly. Use passive adapters.

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GPU Governor

The governor controls GPU frequency and voltage. Required for gaming performance.

Installation

# Fedora/Bazzite (recommended):
sudo dnf copr enable filippor/bazzite
sudo dnf install cyan-skillfish-governor-tt
sudo systemctl enable --now cyan-skillfish-governor-tt.service

# Bazzite (automated script):
curl -s https://raw.githubusercontent.com/vietsman/bc250-documentation/refs/heads/main/oberon-setup.sh | sudo sh

# Arch/CachyOS (SMU - no kernel patch needed):
yay -S cyan-skillfish-governor-smu
sudo systemctl enable --now cyan-skillfish-governor-smu.service

Configuration

Edit /etc/cyan-skillfish-governor-tt/config.toml:

# Safe starting point:
min_frequency = 1000  # MHz
max_frequency = 2000  # MHz
min_voltage = 700     # mV (hard minimum, don't go lower)
max_voltage = 1050    # mV

Restart governor after changes:

sudo systemctl restart cyan-skillfish-governor-tt

Check GPU Frequency

cat /sys/class/drm/card0/device/pp_dpm_sclk
# Should show multiple frequencies, current one marked with *

Without governor, GPU is stuck at 1500MHz = poor performance.

Governor guide →

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Common Commands

System Info

# Check Mesa version
glxinfo | grep "OpenGL version"

# Check GPU
lspci | grep VGA
vulkaninfo | grep deviceName

# Check RAM/VRAM split
free -h
cat /sys/class/drm/card0/device/mem_info_vram_total

# Check temperatures
sensors

# Monitor GPU
nvtop

GRUB Configuration

# Edit boot parameters
sudo nano /etc/default/grub

# Update GRUB (Fedora/RHEL):
sudo grub2-mkconfig -o /boot/grub2/grub.cfg

# Update GRUB (Debian/Ubuntu):
sudo update-grub

# Reboot
sudo reboot

Governor Management

# Check status (use whichever you installed)
systemctl status cyan-skillfish-governor-tt
# Or: systemctl status oberon-governor

# Start/stop
sudo systemctl start cyan-skillfish-governor-tt
sudo systemctl stop cyan-skillfish-governor-tt

# Restart after config change
sudo systemctl restart cyan-skillfish-governor-tt

# View logs
journalctl -u cyan-skillfish-governor-tt -f

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Gaming Performance

Launch Options (Steam)

For most games:

RADV_DEBUG=nohiz %command%

For games with visual glitches:

RADV_DEBUG=nohiz,nocompute %command%

Expected FPS (1080p)

Game	Settings	FPS Range
Cyberpunk 2077	High, FSR	60-90
Control	High, RT off	60+
Control	Medium, RT on	30-40
DMC 5	High	100+
CS2	High	120+
Elden Ring	High	60 (capped)

Game compatibility list →

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Troubleshooting Quick Fixes

No Display

Solution: Boot with nomodeset parameter

# At GRUB, press 'e'
# Add 'nomodeset' to linux line
# Press Ctrl+X to boot

GPU Not Detected

Check:

1. Mesa version ≥ 25.1: glxinfo | grep Mesa
2. Kernel ≤ 6.14: uname -r
3. nomodeset removed from GRUB
4. Governor running: systemctl status cyan-skillfish-governor-tt

BIOS Settings Don't Stick

Solution: Clear CMOS properly

1. Power off, unplug
2. Remove CMOS battery for 60 seconds
3. While battery out, press power button 5 times
4. Replace battery, boot, reconfigure

Game Crashes

Check:

1. VRAM allocation (try 10GB/6GB fixed if using 512MB dynamic with ZRAM)
2. Disable ZRAM: sudo systemctl disable zram-swap
3. Update Mesa to latest
4. Check kernel version (use 6.18.18 LTS, 6.17.11+, or 6.12-6.14 LTS)

High Temperatures

Fix:

1. Check fans spinning: sensors
2. Straighten heatsink fins
3. Replace thermal paste
4. Verify high static pressure fans (3+ mmH2O)

Full troubleshooting →

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Important Warnings

!!!danger "Critical Warnings" 1. Always clear CMOS after USB BIOS flash 2. Disable IOMMU in BIOS (IOMMU is broken - MUST disable) 3. Use nomodeset during install, remove after drivers installed 4. Avoid kernel 6.15.0-6.15.6, 6.17.8-6.17.10 (GPU driver fails), and 6.19.x (PCIe issues) 5. 700mV minimum voltage (GPU locks to 1500MHz below this) 6. Active DP-HDMI adapters break audio 7. ACPI fix is essential — required for C-State support and power management (bc250-acpi-fix) 8. No HW video encode/decode — VCN firmware blocked by Sony, software decoding only 9. Do NOT use Smokeless_UMAF — may cause permanent damage to the board

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Key Community Resources

Official Documentation

• GitHub: https://github.com/mothenjoyer69/bc250-documentation
• BIOS Repo: https://gitlab.com/TuxThePenguin0/bc250-bios/
• Governor: Multiple forks (Oberon, Cyan Skillfish)

Community

• Discord: Active community, link in GitHub
• TheRetroWeb: https://theretroweb.com/motherboards/s/amd-bc-250

Key Contributors

• mothenjoyer69 - Setup scripts
• Average Data Hoarder - Modded BIOS
• Segfault - Oberon Governor
• FilippoR - COPR packages, Bazzite integration

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Need more detail? See the full documentation sections:

• Getting Started
• BIOS Flashing
• Linux Setup
• Troubleshooting