PanelOS

Small USB screens for PC cases are a fun buy. A 3.5-inch panel sits behind the glass, ready to show how hot your CPU is running. What it ends up showing depends entirely on the software feeding it.

PanelOS is a Windows app written for these panels, the Turing Smart Screen and other 3.5-inch USB screens at 480 by 320. The setup it describes is three steps. Plug in the screen, install PanelOS, pick a theme. After that it lives in the system tray, and the screen follows whatever you choose there.

It comes from a solo developer, and that shows in a good way. The help pages answer the questions a builder would really ask, like why the CPU temperature reads zero. The app needs admin rights, set once by the installer, and some PCs also need a sensor driver.

The basics are CPU and GPU temperatures, usage, watts and fan speeds. Around those you get a local clock and weather for a city you set. Now playing follows whatever Windows reports as the current song, with Spotify as a fallback, and there's no Spotify login involved.

There are six themes, with names like Signature, Nature Flow, Noir Editorial and Chronograph. Pro can also put an animated weather scene behind the clock. The screen goes dark when Windows shuts down or sleeps and comes back on wake, which is a nice touch for a PC that sits in a bedroom.

Not sure your panel is supported? The site suggests checking its hardware ID and then trying Lite. If the Classic theme shows up on your screen, every Pro theme will too.

Lite is free. Pro costs $6.99 once, covers two PCs and includes all 1.x updates. The latest version listed in November 2026 is 1.4.3.

Expect a warning when you install. The installer isn't code-signed yet, so Windows SmartScreen may flag it. The developer's explanation is plain: "Signing certificates are expensive for a solo developer." Each release is submitted to Microsoft for review, and the SHA-256 hash of every installer is published in the release notes, so you can check that your download matches. Only download it from the official site.

Two more things to know. The site has no privacy policy, though the app needs no account and the contact form is the only place that asks for a name and email. And PanelOS states it isn't affiliated with any hardware manufacturer.

If there's a small screen in your case doing less than it could, the free Lite download is a low-risk way to see what PanelOS makes of it.