Switch a cheap KVM away from your Linux box, and GNOME or KDE often shuffles your windows the moment you switch back. The fix is a switch with EDID emulation, a hotkey your keyboard can send, and DisplayPort for 4K above 60 Hz.
This guide covers desk KVM switches that share one keyboard, mouse and monitor set between PCs; a server you reach over the network needs an IP KVM, which our IP KVM guide covers. Specs, prices and Linux notes were checked against maker manuals, kernel docs and bug trackers in October 2026, and nothing here was bench-tested.
Start with the quick picks
Each switch below wins one job. Find your desk in the first column:
| Pick | Best for | Video | EDID emulation | Price band |
|---|---|---|---|---|
| TESmart DKS202-M24 | Two monitors, two PCs | DP 1.4, 4K144 | Yes, every input | $360 to $380 |
| TESmart HKS201-P23 | One monitor with EDID | HDMI 2.0, 4K60 | Yes, per input | $120 to $135 |
| UGREEN 25962A | Budget DisplayPort | DP 1.4, 4K240 | No | $50 to $60 |
| TESmart HDK202-M24 | HDMI 2.1 monitors and TVs | HDMI 2.1 out, 4K120 | Yes | $470 to $500 |
| ATEN CS1924A | Four PCs | DP 1.4, 4096×2160 at 240 Hz | No (re-detect toggle) | $390 to $410 |
| Cable Matters 201342 | Two USB-C laptops | USB-C 40 Gbps | Not stated | $95 to $110 |
| UGREEN 30768 USB switch | Software KVM with ddcutil | None in the path | Not needed | $25 to $35 |
Prices come from Amazon US on October 21, 2026, and they move often, so check the current price before you order. Every pick was sold by the maker or its own storefront on Amazon that day, so you are not buying through a reseller of unknown stock.
Check how these were picked
No switch here went through a test bench, so every pick had to clear the same paper checks instead:
- Read the maker spec sheet or manual for ports, refresh rate and EDID
- Check whether Linux appears in the maker’s OS list
- Note which OS the firmware updater needs
- Confirm the Amazon seller is the maker itself
- Search the KDE, GNOME and kernel bug trackers for the model
A few popular names didn’t make it. The Level1Techs DP 1.4 KVM is a Linux community favorite, but it’s sold only on its own store and has no EDID emulation; its FAQ lists 4K120, with higher refresh only through DSC. Watch for a look-alike brand spelled TESmert on Amazon too, because it isn’t the same company.
Compare the specs
Rule switches out fast with this table. The hotkey and firmware columns matter more on Linux than the refresh rate does:
| Switch | PCs x monitors | Hotkey | K&M ports | Linux in OS list | Firmware updater |
|---|---|---|---|---|---|
| TESmart DKS202-M24 | 2 x 2 | Right-Ctrl twice | Pass-through, emulation fallback | Yes | Windows (macOS for some tools) |
| TESmart HKS201-P23 | 2 x 1 | Right-Ctrl, Scroll Lock or Left-Ctrl | Pass-through | Yes | Windows |
| UGREEN 25962A | 2 x 1 | None (button, desk puck) | Plain USB hub | Yes | None published |
| TESmart HDK202-M24 | 2 x 2 | Hotkey, IR, UART | Pass-through, legacy mode | Yes | Windows |
| ATEN CS1924A | 4 x 1 | Scroll Lock twice (Ctrl twice alt) | Emulation with bypass | Yes | Windows |
| Cable Matters 201342 | 2 x 1 | None (RF remote) | Monitor or dock hub | Not mentioned | None mentioned |
Buy the TESmart DKS202-M24 for two monitors
The DKS202-M24 is the one to buy if you run two monitors and hate the window shuffle. It keeps an EDID emulator on every input, on by default, so each PC thinks its monitors never left. That is the whole fix for GNOME and KDE rearranging windows, because the compositor never sees an unplug.
Set it up in this order:
- Connect two DP 1.4 cables from each PC; outputs run 4K144, or 4K165 and 8K60 with DSC
- Plug the keyboard and mouse into the dedicated K&M ports, which pass through by default
- Switch with Right-Ctrl twice, the front button or the IR remote; mouse-wheel switching is off until you press Right-Ctrl, Right-Ctrl, F6
- Toggle EDID emulation for all inputs at once with Right-Ctrl, Right-Ctrl, F5 if a monitor misbehaves
TESmart lists Debian, Ubuntu and Fedora, and says VRR and G-Sync or FreeSync pass through alongside EDID. Nobody has published a Linux test of that combination, so treat it as the maker’s claim until you see it on your own desk. Skip it if you can’t borrow a Windows or macOS machine for firmware updates, and check stock first, since the Amazon listing showed a later ship date on October 21.
Pick the TESmart HKS201-P23 for one monitor
The HKS201-P23 is the cheapest switch here with per-input EDID emulation, so it’s the safe Linux choice for an office desk with one 4K monitor. It’s HDMI 2.0, which means it tops out at 4K60 with 4:4:4 color and HDR10.
You can set the hotkey trigger to Right-Ctrl (the default), Scroll Lock or Left-Ctrl, so compact keyboards work without remapping. The IR remote and Auto Scan cover the times you’d rather not touch the keyboard, and audio, a microphone and USB 3.0 run through it as well. Skip it if you game above 60 Hz or your monitor only has DisplayPort.
Save with the UGREEN 25962A
The UGREEN 25962A runs DP 1.4 at up to 4K240 or 8K60 for a fraction of the TESmart price. UGREEN is upfront about the catch: it doesn’t support hotkey switching or EDID emulation. You switch with the button or the wired desk puck, and four USB 5 Gbps ports come along. It draws power through the USB cables to both PCs, which UGREEN says must both be connected; the 5 V input port has no cable or adapter in the box.
Skip it if you keep a lot of windows open all day, because GNOME and KDE often move them when the monitor drops on every switch. On a single-monitor desk that you mostly use full screen, the reshuffle costs little, and the budget switch is fine.
Choose the TESmart HDK202-M24 for HDMI 2.1
The HDK202-M24 is for HDMI 2.1 monitors and TVs. Each PC feeds one HDMI 2.1 and one DP 1.4 input, and both outputs are HDMI 2.1 with dual 4K120 at 12-bit, VRR and ALLM. It has EDID emulation and UART control, and TESmart lists Linux, including Raspberry Pi.
It also has a fan with four modes, which you’ll hear on a quiet desk. Skip it if you run an AMD GPU on an older kernel, because HDMI 2.1 FRL landed in Linux 7.2 behind a flag and only the unreleased 7.4 turns it on by default. On AMD with a distro kernel, a DisplayPort switch is the simpler path.
Run four PCs on the ATEN CS1924A
The CS1924A shares one DP 1.4 monitor between four PCs, at up to 4096×2160 at 240 Hz or 8K60. ATEN names Linux explicitly in its OS table, though that table lists old distro releases. Set it up like this:
- Press Scroll Lock twice to switch, or set Ctrl twice if your keyboard has no Scroll Lock
- Try turning keyboard emulation off (HSM, then N) if a gaming keyboard misbehaves; that also disables several hotkeys
- Leave mouse emulation on if you want mouse-wheel port switching
- Use RS-232 for scripted switching; the remote port selector is a wired button
Skip it if you need EDID emulation, because it only offers a Monitor Re-detection toggle that is off by default. Firmware updates need Windows, and it was new and scarce on Amazon in October 2026, so check stock before you build a desk around it.
Share a USB-C dock with the Cable Matters 201342
The Cable Matters 201342 switches one USB-C monitor or dock between two laptops at 40 Gbps. It passes up to 140 W of USB-C power to whichever laptop is active, and you switch with a button or the RF remote. Cable Matters lists no software or utility for it, which suits Linux laptops.
Cable Matters doesn’t mention Linux, though, so read this as an inference: it should work on any laptop whose USB-C port carries DP Alt Mode or Thunderbolt, such as the machines in our Framework vs ThinkPad comparison. Skip it if a laptop’s USB-C port has no video output or your dock has a captive host cable. Our Thunderbolt 4 dock guide covers how docks behave on Linux.
Build a software KVM with ddcutil
The Linux-only trick skips the video switch entirely. A UGREEN 30768 USB 3.0 switch moves the keyboard and mouse, and the monitor changes input over DDC/CI. Nothing sits in the video path, so you keep full refresh rate, VRR and HDR at any resolution, because each PC stays connected to its own monitor input the whole time.
Install ddcutil from your distro repos on each PC, then load the i2c-dev module and keep it loaded across reboots:
sudo modprobe i2c-dev
echo i2c-dev | sudo tee /etc/modules-load.d/i2c-dev.confCheck that the monitor answers DDC/CI. Run it with sudo, or add your user to the i2c group your distro creates:
sudo ddcutil detectThen switch the monitor input by its VCP 0x60 value. The ddcutil FAQ lists 0x0f as DisplayPort-1 and 0x11 as HDMI-1, but your monitor may use different values; add --display 2 when more than one monitor is attached:
sudo ddcutil setvcp 60 0x0fTo make it automatic, display-switch runs on each PC and sends that command when the USB switch moves. On DisplayPort, the input you leave can go dark, so you may not be able to switch back from the same PC. Test that before you return a hardware KVM you already own.
Check for EDID emulation first
Without EDID emulation, the PC sees the monitor unplug on every switch, and the compositor tears the output down. GNOME and KDE restore the monitor layout but not always every window, and KDE bug 470799 shows a Level1Techs DP 1.4 KVM on Plasma Wayland coming back with a black wallpaper. If you keep a lot of windows on a second monitor, pay for EDID emulation.
A black screen or 640×480 through a KVM is a different problem. The kernel EDID docs name KVMs as a use case for loading a saved EDID with a kernel parameter like this:
drm.edid_firmware=DP-1:edid/mon.binThat fixes a wrong or missing EDID, but it does not stop the unplug event, so it won’t stop windows moving. Save the EDID while the monitor is plugged straight into the PC. List /sys/class/drm first and use the exact cardN path, since a second GPU adds another DP-1; the connector name must match the one in the parameter:
ls /sys/class/drm/
sudo mkdir -p /usr/lib/firmware/edid
sudo cp /sys/class/drm/card1-DP-1/edid /usr/lib/firmware/edid/mon.binAdd the parameter to GRUB_CMDLINE_LINUX in /etc/default/grub, then run sudo update-grub on Debian and Ubuntu or sudo grub2-mkconfig -o /boot/grub2/grub.cfg on Fedora and RHEL. Include the .bin file in the initramfs as well (a dracut install_items line or an initramfs-tools hook), or the early boot screen will still come up blank.
When your switch has no EDID emulation, reapply the monitor layout after each switch instead. This restores monitor positions, not window positions. On KDE, list the outputs first:
kscreen-doctor -oThen set the positions, here with a 2560-pixel-wide DP-1 at 100% scale on the left and DP-2 to its right; Plasma Wayland uses scaled coordinates:
kscreen-doctor output.DP-1.position.0,0 output.DP-2.position.2560,0GNOME 48 and later ship gdctl for the same job, which rules out Ubuntu 24.04 LTS with its older GNOME. This makes DP-1 primary with DP-2 to its right:
gdctl set --logical-monitor --primary --monitor DP-1 --logical-monitor --monitor DP-2 --right-of DP-1Pick DisplayPort for 4K above 60 Hz
DisplayPort is the low-risk choice on Linux for high refresh, because HDMI 2.1 on AMD needs Linux 7.2 or later with amdgpu.dcfeaturemask=0x402 (the FRL bit plus the default bit) until 7.4 makes it the default. Budget two DP cables per PC for dual-monitor switches; TESmart’s FAQ for its USB-C CKS202-P23 model says single-cable MST mode isn’t supported on Ubuntu. NVIDIA’s proprietary driver also gives monitors behind an MST hub no I2C bus, so ddcutil can’t reach them.
Match the hotkey to your keyboard
Hotkeys only work on the switch’s dedicated keyboard ports, and the trigger key has to exist on your board. Compact keyboards often drop Scroll Lock, so set the trigger to Right-Ctrl. QMK and other NKRO keyboards may need NKRO turned off for hotkeys to register.
TESmart’s help pages say, word for word, “We recommend keeping Passthrough Mode on at all times unless using Linux”, and they do not say why. Try pass-through first anyway, since emulation is the fallback if hotkeys fail. Our keyboard and mouse guide covers compact boards.
Plug gaming mice into the pass-through port
Emulated ports present a generic keyboard and mouse to each PC, so extra buttons and DPI keys can stop working. Tools like Solaar, Piper and OpenRazer need to see the real device, which means the pass-through or USB 3 port. Every USB device drops and comes back when you switch, so keep drives and audio interfaces off the switched hub.
Test DDC/CI before you rely on it
No maker on this list documents DDC/CI pass-through. That matters on KDE, because the Plasma brightness slider uses libddcutil, so a KVM that drops DDC breaks it. Our monitor guide shows the ddcutil brightness setup, which doubles as a quick DDC test through the switch.
Keep a Windows box for firmware
ATEN and TESmart firmware updaters run on Windows, and TESmart also offers macOS for some tools. UGREEN lists no KVM firmware on its download pages and Level1Techs ships none, so buy for the firmware the switch ships with rather than a promised fix.
Run ddcutil detect through your new KVM in the first week, while the return window is still open.
