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BIOS Overclocking Guide

Overclocking the BC-250 GPU beyond the default 1500 MHz lock.

Quick Start

Most users only need to install a governor. The governor unlocks the GPU from its 1500 MHz lock and enables dynamic frequency scaling up to 2000-2230 MHz.

  1. Install a governor → Governor Setup
  2. Tune voltage/frequency in governor config (see below)
  3. Only patch kernel if needed — Bazzite is pre-patched, SMU governor bypasses patches entirely

Requirements

  • GPU Governor — required for frequency scaling (see Governor Setup)
  • Active cooling — high static pressure fan (Arctic P12 Max or equivalent)
  • PSU — 250W+ on 12V rail for overclocked workloads

What Can Be Overclocked

  • GPU Frequency: 1500 MHz (locked) → 2000-2230 MHz (with governor)
  • GPU Voltage: 700-1129 mV (stock kernel OD_RANGE)
  • Memory: Adjustable via community Mem Timing Utility (advanced — incorrect settings will crash the system)

GPU Frequency Range Kernel Patch

The kernel patch extends the GPU frequency range from 1000-2000 MHz to 350-2230 MHz.

Created by: ViRazY (GitHub)

Most Users Don't Need to Manually Patch

  • Bazzite/PikaOS: Kernel already includes this patch.
  • Any distro: The cyan-skillfish-governor-smu bypasses the need for kernel patches entirely via SMU firmware calls.
  • Manual patching is only needed for non-Bazzite users who want to use the TT governor or manual sysfs overclocking with extended frequency range.

What the Patch Does

  • Default range: 1000-2000 MHz → Patched range: 350-2230 MHz
  • Voltage range: 700-1129 mV (unchanged by standard patch)
  • Allows idle downclocking to 350 MHz for lower power draw
  • Extended voltage patch (600-1300 mV) exists but is NOT recommended

Pre-Patched Distributions (Easiest)

  1. Bazzite - Kernel pre-patched, no compilation needed

  2. Download: Bazzite Kernel Releases

  3. Arch Linux (AUR packages)

  4. linux-bazzite-bin - Bazzite kernel for Arch

  5. linux-lts-amd-bc250-headers - BC-250 LTS kernel

  6. PikaOS - Includes GPU frequency patch by default

Manual Download

The patch file is available in the BC-250 Discord server: - Forum thread: bc250-resources → "Increased GPU frequency range kernel patch" - File: linux-6.12-bc250-freq.mypatch (639 bytes)

Manual Application

# Clone linux-tkg repository
git clone https://github.com/Frogging-Family/linux-tkg.git
cd linux-tkg

# Create userpatches folder
mkdir linux612-tkg-userpatches

# Download and place patch
# (Get linux-6.12-bc250-freq.mypatch from Discord)
mv linux-6.12-bc250-freq.mypatch linux612-tkg-userpatches/

# Compile kernel
# Follow linux-tkg instructions
# Press Y when asked to apply userpatches

Benefits: - Automatic patch application - Gaming-optimized tweaks included - Well-tested compilation process

Method 2: AMDGPU Module Only (Fast Method)

Instead of 3-hour full kernel build, compile just the amdgpu module in 3 minutes:

Trade-off: Loads an out-of-tree module (taints kernel)

Process: 1. Download kernel source matching your running kernel 2. Apply patch to cyan_skillfish driver files 3. Build only amdgpu module 4. Load patched module

Note: The patch modifies only 3 values in the cyan_skillfish file.

Method 3: Distribution-Specific

Fedora: 

# Follow Fedora's kernel patching guide
# Or install Bazzite kernel RPMs directly

Arch Linux: 

# Use AUR packages (recommended)
yay -S linux-bazzite-bin
# Or linux-lts-amd-bc250-headers

# Or apply patch to PKGBUILD for custom builds

Verifying the Patch

Check if patch is applied:

cat /sys/devices/pci0000:00/0000:00:08.1/0000:01:00.0/pp_od_clk_voltage

Expected output should show frequency range 350-2230 MHz.

Troubleshooting: GPU Locked at 1500 MHz

If GPU remains at 1500 MHz after installing patched kernel:

  1. Verify patch applied:
  2. Try setting frequencies in unpatched range (1000-2000 MHz) via governor
  3. If works: Patch NOT applied, rebuild kernel

  4. If doesn't work: Governor issue, not patch

  5. Update governor configuration: 

    # For cyan-skillfish-governor-smu:
sudo nano /etc/cyan-skillfish-governor-smu/config.toml
# Update safe-points to include extended range frequencies

sudo systemctl restart cyan-skillfish-governor-smu

Maximum Performance: 

frequency:
  min: 1000
  max: 2230
voltage:
  min: 700
  max: 1060    # Adjust based on stability (1000-1060 typical)

Balanced Profile: 

frequency:
  min: 1000
  max: 2000
voltage:
  min: 700
  max: 1000

Low Power Profile: 

frequency:
  min: 350     # Deep idle
  max: 2000
voltage:
  min: 700     # Don't go below 700 mV
  max: 1000

Compatibility

Kernel Versions: - Tested: 6.12 (original), 6.15, 6.16.x - Expected: Works on newer kernels (driver-level patch)

Distribution Support:

Distribution Status Method
Bazzite ✅ Pre-patched Use stock kernel
Arch (AUR) ✅ Pre-patched Install from AUR
PikaOS ✅ Pre-patched Use stock kernel
Fedora ⚠️ Manual linux-tkg or Bazzite RPM
CachyOS ⚠️ Manual May be included in future
Manjaro ⚠️ Manual No pre-built packages
Debian ⚠️ Manual Patch kernel source

Warnings

Cooling Required at 2230 MHz

2230 MHz @ 1050 mV generates significantly more heat than stock. Ensure high static pressure cooling (Arctic P12 Max or Noctua NF-A12x25). Temperature monitoring essential.

Silicon Lottery

Not all chips stable at 2000 MHz @ 1000 mV. Voltage requirements for 2230 MHz vary (1000-1060 mV typical). Test stability incrementally.

PSU Requirements

Maximum power draw can exceed 320W with full GPU load (Furmark). Ensure adequate PSU capacity. Games typically draw 220-250W max.

Minimum Voltage: 700mV

Setting minimum voltage below 700mV locks the GPU to 1500MHz. Always keep min voltage ≥700mV.

Do NOT: - Use extended voltage patch (600-1300 mV) - unnecessary and risky - Go below 700 mV (locks GPU to 1500MHz, defeats the purpose of overclocking) - Exceed 1129 mV without careful testing (hardware degradation risk) - Use Smokeless_UMAF — may cause permanent damage to the board

CPU Overclocking & Undervolting (SMU Tool)

A community-developed SMU (System Management Unit) tool enables CPU overclocking and undervolting on the BC-250.

Repository: bc250-collective/bc250_smu_oc Created by: mrfrakes and dantistnfs (via SMU reverse engineering)

What It Does

  • Overclock all 6 CPU cores (up to 4 GHz @ 1275 mV reported)
  • Undervolt the CPU for lower power and temperatures
  • Detect viable overclock for your specific board
  • Apply overclock automatically on startup

Requirements

  • Cooling: Good active cooling is essential — CPU overclocking adds significant heat on top of GPU load
  • PSU: Ensure adequate headroom (300W+ recommended when combined with GPU overclock)
  • Testing: Use incremental steps and stress test thoroughly

Silicon Lottery

Not all BC-250 boards will reach 4 GHz. Use the tool's detection features to find your chip's safe limits. Always test stability under sustained load before committing settings.

Safe Overclocking Limits

Start at 2000 MHz @ 1000 mV and work up. Stability varies by board (silicon lottery). Maximum achievable frequency depends on your cooling solution:

Air Cooled (conservative):

  • 2000 MHz @ 1000 mV — safe starting point for most boards
  • 2100-2175 MHz @ 1025-1050 mV — works on many boards, test thoroughly
  • 2230 MHz @ 1060 mV — conservative air-cooled maximum

Good Air Cooling (Arctic P12 Max or better):

  • 2300 MHz @ 1075 mV — achievable with high static pressure fans and good case airflow

Liquid Cooling:

  • 2400 MHz @ 1125 mV — per NexGen3D testing with liquid cooling setup

Manual Overclocking

Method 1: Via sysfs (Temporary)

Test frequencies before making permanent:

# View current frequency/voltage table
cat /sys/class/drm/card1/device/pp_od_clk_voltage

# Set voltage and frequency
# Format: vc <level> <frequency_MHz> <voltage_mV>
echo "vc 0 2100 1025" | sudo tee /sys/class/drm/card1/device/pp_od_clk_voltage

# Commit changes
echo "c" | sudo tee /sys/class/drm/card1/device/pp_od_clk_voltage

# Verify
cat /sys/class/drm/card1/device/pp_od_clk_voltage

Test with benchmark: 

# Run Unigine Superposition or game for 30+ minutes
# Monitor temperatures and stability

Method 2: Via Governor Config (Permanent)

Edit config: 

sudo nano /etc/cyan-skillfish-governor-smu/config.toml

Multi-voltage point configuration: 

safe-points = [
    [1000, 700],   # 1000 MHz @ 700 mV
    [1500, 900],   # 1500 MHz @ 900 mV
    [2000, 1000],  # 2000 MHz @ 1000 mV
    [2100, 1025],  # 2100 MHz @ 1025 mV
    [2175, 1050],  # 2175 MHz @ 1050 mV (overclock)
    [2300, 1075],  # 2300 MHz @ 1075 mV (good air cooling)
]

Restart governor: 

sudo systemctl restart cyan-skillfish-governor-smu

Testing Stability

Stress Testing

1. Unigine Superposition (Recommended): 

# Download from: https://benchmark.unigine.com/superposition

# Run benchmark
# 1080p Extreme preset
# Loop for 30+ minutes

2. Gaming Stress Test: - Run demanding game for 60+ minutes - Test different scenarios (loading screens, open world, combat)

3. Monitor During Testing: 

# Watch sensors
watch -n 1 sensors

# Check for:
# - GPU temp < 85°C (< 80°C better)
# - No crashes or artifacts
# - Stable frame rates

Signs of Instability

Reduce frequency or increase voltage if: - System crashes/freezes - Visual artifacts (flickering, black textures, corrupted graphics) - Performance degradation - GPU temp > 90°C

Performance Notes

Overclocking from 2000 to 2230 MHz gives diminishing returns — expect single-digit percentage gains in most games, with significantly higher power draw and temperatures. Most users will see better results from stable governor tuning at 2000-2100 MHz than pushing for maximum clocks.

Voltage Tuning

Undervolting for Efficiency

Goal: Reduce voltage while maintaining frequency

Process: 1. Start at stock frequency (2000 MHz @ 1000mV) 2. Reduce voltage by 25mV (to 975mV) 3. Test stability 4. If stable, reduce another 25mV 5. If crashes, increase by 25mV 6. Find minimum stable voltage

Results vary by board. Test stability thoroughly at each step.

Overvolting for Higher Clocks

Use Case: Pushing beyond 2100 MHz

Caution: - Higher voltage = more heat and power - Diminishing stability gains above 1050mV - Risk of hardware degradation

Safe limits: - Maximum recommended: 1085mV - Absolute maximum: 1100mV (high risk)

Cooling and Power

Higher clocks mean more heat and power draw. Keep GPU below 85°C under load. See Cooling Solutions and Power Requirements for details.

Before overclocking: Ensure you have a governor installed, adequate cooling, and a PSU rated for 250W+ on 12V rail. Increase frequency in 50-100 MHz steps, testing stability for 30+ minutes at each step.

Troubleshooting Overclocking Issues

System Crashes Immediately

Cause: Voltage too low for frequency

Solution: - Increase voltage by 25-50mV - OR reduce frequency by 50-100 MHz

Crashes After 10-30 Minutes

Cause: Thermal throttling or marginal stability

Solutions: 1. Check temperatures (should be < 85°C) 2. Improve cooling 3. Increase voltage slightly 4. Reduce frequency

Visual Artifacts

Symptoms: - Black textures - Flickering - Corrupted graphics

Causes: - Memory clock too high (not adjustable) - Unstable frequency/voltage - Overheating

Solutions: - Reduce GPU frequency - Add RADV_DEBUG=nohiz to environment - Check cooling

Performance Worse After Overclock

Possible Causes: 1. Thermal throttling (too hot) 2. Power limit hit (PSU insufficient) 3. Hitting frequency that triggers instability

Solutions: - Check temperatures - Verify PSU wattage - Try different frequency

Governor Not Applying Overclock

Check: 

# Verify governor running (use whichever you installed)
systemctl status cyan-skillfish-governor-smu
# Or: systemctl status cyan-skillfish-governor-tt

# Restart governor
sudo systemctl restart cyan-skillfish-governor-smu

# Check applied settings
cat /sys/class/drm/card1/device/pp_od_clk_voltage

Advanced: Multiple Voltage Points

For Cyan-Skillfish Governor or manual tuning:

Create voltage curve:

  1. Test each frequency point: 

    # Test 1500 MHz
echo "vc 0 1500 875" | sudo tee /sys/class/drm/card1/device/pp_od_clk_voltage
echo "c" | sudo tee /sys/class/drm/card1/device/pp_od_clk_voltage
# Run benchmark, find minimum stable voltage

# Test 1750 MHz
echo "vc 0 1750 950" | sudo tee /sys/class/drm/card1/device/pp_od_clk_voltage
echo "c" | sudo tee /sys/class/drm/card1/device/pp_od_clk_voltage
# Run benchmark, find minimum stable voltage

# Repeat for 2000, 2100, 2175, 2230 MHz

  2. Record stable voltage for each frequency

  3. Add to governor config

Benefits: - More efficient (lower voltage at mid frequencies) - Better temperature management - Smoother frequency transitions

Time Investment: - Testing each frequency point thoroughly - Recording stable voltages - Validating with benchmarks

Community Resources

Last Updated: 2026-03-18