Barrier looks great, but does anyone know why KVM switches with DisplayPort or HDMI are so outrageously expensive? It should just be a switch, no complex electronics, so I truly can't figure out why any KVM should cost more than say $30-50 US.

I suspect DRM or patents for rent seekers are involved somehow. Or maybe they're playing on the naivety of the business community towards this stuff. I'd sure like to know, and also if there are any low-cost or open source KVMs available.

> It should just be a switch, no complex electronics

For any high-bandwidth thing like HDMI, you need to do clock recovery and copy over the bitstream at the very least. You can't just use relays or whatever. Doing this at 10gbps+ is going to cost a bit.

spicybright

I don't see that much of a reason you can't do a relay to "disconnect" one hdmi and plug in another.

The computers would see the HDMI cable/USB cords unplugging and re-plugging.

Obviously this can be problematic, but I can't see it being that expensive.

mikepurvis

Even outside of impedence issues, you can't just use relays because then every switch is basically an unplug/replug, meaning that:

a) the display will flip out and spend multiple seconds re-syncing itself, and

b) the sources may take actions such as resizing the desktop, switching to the internal display, pausing the game, whatever.

Part of the point of a hardware KVM is that it negotiates its own connection to all of the devices involved, and only changes which signals are passed through at any given moment, resulting in instantaneous switchovers.

Now, a multi-input monitor can also do this, but then you have to deal with whatever compat issues are involved in commanding it to switch over DDC (see for example https://github.com/haimgel/display-switch), and it typically also won't be as fast as a hardware solution since input switching speed isn't a metric most people care about when monitor shopping.