July 8, 2026
My complete guide for setting up the ASRock BC-250. You can’t beat its price for performance, and it’s perfect for those who love projects.
TLDR (for those with BC-250 experience):
- Use 6GB VRAM allocation: it still dynamically allocates, and some games will have terrible texture quality if you use 512MB like everyone recommends. It will take a chunk of your usable system RAM away, but it won’t matter.
- Disable Steam precached shader downloading: this needs to be recommended more! With it enabled you download a generic shader cache that doesn’t match the BC-250. Every-time you launch your game it will redownload, overwriting any background processed shader cache that the BC-250 generated.
- Undervolt & overclock CPU: there is no reason not too! With the 40CU unlock, that leaves extra room for CPU overclocking. Try to get 4Ghz if you can, (I can only reach 3.8).
- Bazzite Users- Disable HHD daemon: causes constant stuttering every couple of seconds. Noticed this issue, when basic 2D games seemed to have consistent lag spikes.
For those looking for a full guide, with all the juicy tips and tricks, please continue…
BIOS Flashing
VRAM allocation
- 512MB is recommended by most.
- 6GB is my recommendation.
Chipset -> Integrated Graphics Controller -> Forces
- UMA Mode -> UMA_SPECIFIED
- UMA Frame buffer Size -> 6GB
Cooling
Don’t bother with buying two fans. Only one really makes a difference. See very helpful Reddit post.
- Artic P12 Pro (recommended)
- Noctua NF-A12x25 (less pressure than Artics, still do the job perfectly fine tho)
Set fan-curve in the bios.
GPU Governor
Out of the box, the BC250 GPU is locked to 1500MHz. The cyan-skillfish-smu GPU governor allows for dynamically scaling the GPU clock speeds to match demand. Highly recommended for both decreasing idle power usage, and dramatically increasing game performance.
Installation
Cachy OS installation:
yay -S cyan-skillfish-smu
Bazzite installation:
sudo dnf copr enable filippor/bazzite
sudo rpm-ostree install cyan-skillfish-governor-smu
systemctl reboot
Configuration
Once installed, edit the config file: /etc/cyan-skillfish-smu/config.toml
These are extremely safe defaults, meant to work on everyone’s BC250. However, there’s a good chance you can squeeze out more performance with less power while also improving your system’s thermals.
Frequency Range
[frequency-range]
min = 1000 # MHz (350 is the absolute minimum good silicon can go)
max = 1850 # MHz
Begin with updating the frequency-range. The max of 1850 MHz is a sweet spot once you enable the additional GPU CUs (compute units) in the next step. Going beyond it doesn’t improve performance much and only dramatically increases power-draw and heat. If you don’t enable extra CUs, then you’ll need to bump the max MHz to 2000 (safe) and up 2200 MHz if you can. But realistically there is no reason to do this once you enable the additional CUs.
We’ll start by lowering the minimum frequency-range. This will improve power-draw on idle and in less-demanding games. Follow the process below.
Keep repeating the below steps until your system becomes unstable and crashes:
- Decrease minimum frequency-range in increments of 100.
- Save & exit the config.
sudo systemctl restart cyan-skillfish-smu
I was lucky enough to have a system stable at 350MHz. But your milage may vary.
Load Targets
Next, I like to adjust the load-target values. This is entirely personal preference, feel free to skip. These are percentage values of GPU utilization. Upper defines at which percentage the GPU must be used to clock up. Lower defines the percentage of utilization for clocking down. The defaults are very unwilling to clock down, even in lesser demanding games.
# %
[load-target]
upper = 0.65
lower = 0.35 # Default is 0.50
These settings work perfect for me. It cranks the GPU just enough for less demanding games without giving it more power than it needs.
Safe-point voltages
You’ll find safe-points defined for many GPU frequencies. Again, the voltages are very safe defaults, you can probably get away with lowering many of them to achieve better thermals and lower power without compromising performance.
Work through them one at a time. Drop it by increments of 50mV. Then test each frequency to ensure system stability. This example forces the GPU to a fixed frequency of 500 MHz.
cyan-skillfish-performance-mode --fixed-frequency 500
To ensure that frequency applied run this command:
cat /sys/class/drm/card1/device/pp_dpm_sclk
The current GPU frequency is the one with the (*). Continue decreasing the voltage by 50mV until the system becomes unstable; then revert to last working config and move on to the next safe-point voltage value. Once you are finished, you should have a stable highly optimized experience tuned to your BC-250.
Once you are done testing specific frequencies, disable performance mode.
cyan-skillfish-performance-mode --off
Allow GPU Governor to automatically start on boot
Now that all your settings are dialed in, we are safe to have them persist on boot.
sudo systemctl enable --now cyan-skillfish-smu
Make sure that your settings are stable before enabling, otherwise you’re gonna have a bad time if you get stuck crashing on every reboot.
40CU Unlock
By default the BC-250 ships with 24 CUs (compute units) on the GPU. In comparison the PS5 ships with 36 CUs. These binned crypto boards were stripped down, however the underlying hardware is still there–we just need to enable them.
Not all boards are created equally, some may work with all 40 CUs perfectly, others will only work with 38 or 36. Either way there’s lots of performance and better efficiency to be had by enabling these units.
BC250 Live Manager allows us to enable CUs on the fly.
Installation
Download the official script and make it an executable:
curl -L -o bc250-cu-live-manager.sh https://raw.githubusercontent.com/WinnieLV/bc250-cu-live-manager/refs/heads/main/bc250-cu-live-manager.sh
chmod +x bc250-cu-live-manager.sh
Start the interactive UI:
sudo ./bc250-cu-live-manager.sh
On Bazzite, it will ask you to install UMR, luckily it will run you through the installation process in the interactive UI.
On CachyOS install it from the AUR:
Once installed you can start the interactive UI again.
Enabling CUs
To quickly figure out if you won the silicon lottery, press ‘f’ to enable all CUs. You’ll know very quickly whether you did. If your system didn’t crash or freeze, you won! And you are safe to press ‘w’ to write the table and ‘i’ to install the service (to apply settings on boot).
If you weren’t so fortunate, you need to test each pair of CUs individually until you find the faulty one(s). Once you do just leave them blank and don’t enable them. After working your way through all the CUs and found a stable config, write the table and install the service.
Congradulations! Enjoy the free performance and power efficiency gains!
CPU overclock & undervolt
bc250-smu-oc tool allows users to overclock and undervolt their CPUs.
Installation
Download stress Dependency
CachyOS:
Bazzite (yes, there’s a lot more steps):
Navigate to fedora.pkgs.org. Search for “stress” and find the matching Fedora release (probably 44 or 43). Click the x86_64 rpm package to go to its page. Scroll to the bottom and find the “Download” section, then copy the “Binary Package” link.
Download the stress RPM package to a temporary folder:
mkdir /tmp/stress
cd /tmp/stress
wget <PASTE LINK>
Extract the RPM package to retrieve the underlying binary:
7z x stress-*.x86_64.rpm
7z x stress-*.x86_64.cpio
Copy the binary to the a writable location. If ~/.local/bin doesn’t exist, create it with mkdir -p ~/.local/bin
sudo cp usr/bin/stress ~/.local/bin/stress
Run stress to ensure that stress is available and ready to use. You should see a list of available commands.
Install bc250-smu-oc Utility
Now that the dependencies are installed, we an install bc250-smu-oc:
git clone https://github.com/bc250-collective/bc250_smu_oc.git
cd bc250_smu_oc
pip install .
Bazzite users:
The script is hardcoded to read the stress binary at /usr/bin/stress since it doesn’t exist, the program errors out. To fix this, edit stress_helper.py.
Change this:
_process = subprocess.Popen(["stress", "--cpu", "12"], ...
To this:
_process = subprocess.Popen(["/home/[YOUR_USERNAME]/stress", "--cpu", "12"], ...
Now that the bc250-smu-oc packages are installed, we are ready to begin overclocking & undervolting!
Optimal Overclock Detection
Stress will be used to stress-test the CPU and evaluate the most optimal overclock settings that are stable for your BC-250. It will also calculate how far it can undervolt and be stable.
bc250-detect --frequency 4000 --vid 1275 --keep
If this command crashes, try re-running the command with --vid 1300. If it still is not stable, reduce the target frequency. To be easy on your system, you should stay below 1300 mV Vid.
If you wish not to overclock but only undervolt you may use these settings to stay at stock frequency.
bc250-detect --frequency 3500 --vid 1000 --keep
After your detection completes, you will have a overclock.conf file. Give it a look! These are the results I got.
[overclock]
frequency = 3800
scale = -34
max_temperature = 90
Disable downloading pre-compiled shader-cache
By default the system allows for up to 1GB of shader-cache to be compiled. After that it forgets old shader-cache and rebuilds the new ones on top of it. Heavy games will require more shader cache so I’ll increase the max shader-cache size.
Edit /etc/environment add this line:
MESSA_SHADER_CACHE_MAX_SIZE=5G
I like to give it 5GB, but feel free to bump it up. This is just the max potential size of the shader-cache, so you aren’t wasting any space by raising it right now.