giqles / check-your-temps

Some hacky python + micropython to display PC CPU + GPU temperatures on an external OLED display

Check your temps

This project displays your CPU + GPU temperature using a Raspberry Pi Pico with an OLED screen. It was built for a one-off Christmas gift, don't expect too much in the way of stability or execution.

Display

I used a Raspberry Pi Pico with Pre-soldered Headers (£6) and this 1.3" 64x128 OLED Screen (£8.50). I also used a down-angled micro-USB cable (£5) for aesthetics but really any micro-USB cable would be fine.

You'll probably want Thonny to set up the pico for MicroPython, and copying the files in pico/ on to the pico.

Windows App

There's two parts to this. You need to get the app, then configure it to run on when you logon.

Get the app

Easiest option is to use the latest release on GitHub.

Building from source

If you want to rebuild from scratch you need to have virtualenv. Then install the dependencies using:

python -m virtualenv .venv
.venv/Scripts/activate.bat
pip install -r requirements.txt

Then run:

pyinstaller --clean --add-data "OpenHardwareMonitorLib.dll;." check_your_temps.py

You should find the package constructed under the dist/ subdirectory. You'll also have a build/ subdirectory.

Some issues you might run into

To use OpenHardwareMonitorLib.dll, you might find you need to unblock it first.

When you build the installer, it might trigger alerts from antivirus software. That seems to be a common issue with pyinstaller. I've implemented the easy suggestions in that thread.

If you have been running the app and want to make changes, you might need to disable any scheduled tasks and reboot first. If you don't, you can end up with a file in the dist/ subdir that you can't delete.

Run the app when you log on

To do this, set up the app to run as high-permission background task on your system. For some reason accessing the CPU temperature needs administrator permissions.

Launch a Command Prompt as Administrator. Then run (updating the path to the location on your system):

schtasks /create /sc ONLOGON /tn checkmytemps /tr C:\FULL\PATH\TO\check_your_temps.exe /ru SYSTEM

That will make a scheduled task to run on log on called 'checkmytemps'. The task will run check_your_temps.exe with System-level (ie very high) permissions. You can view the task by searching for 'Task Scheduler' in the start menu. You can also manually start it from this interface. (Right-click --> Run)

The task can be a bit fragile. You can make it a bit more resilient by opening the task from Task Scheduler, going to settings, and making it retry when failed up to some number of times. I set 3. There's probably a way to do this from the CLI as well.

If you want to view the process itself, you'll see it under background tasks in task manager. On my system it uses about 25MB of RAM, and about 0.1% of a CPU core.