First up, an apology – this post has nothing to do with PCs or DNA. Mind you it may make your life easier and/or save you a few quid if you work with multiple PCs so perhaps I shouldn’t apologize after all. 🙂
I know, it’s old hat – KVM switch boxes have been around for donkeys years and I’ve even owned a few of them. They’re pretty cool and froody and are an elegant solution to the problem of having too many monitors, keyboards, mice and even speakers piled up all over the place ..complete with the inevitable rats nest of cables that goes with it.
A few years back (when the only tablets were those that could be swallowed with a glass of water) PC connections to monitors were a lot simpler. Generally everything was connected up using VGA (aka D-Sub) cables with maybe the odd DVI cable. Nowadays we’ve got a mix of VGA, DVI and HDMI.

The above picture was taken from an article that you may want to read – it will explain more about the different connection types, in case you are curious.
This is all well and good until you start shopping around for switch boxes. You might get by using various adapters (possibly reducing the quality of your video in the process) but there’s another option.
If your monitor has several inputs you might be able to use them together, having one PC connected via VGA, another via DVI and a third by HDMI. This will work but switching the active input will involve using the menu on your monitor, which quite frankly is a pain in the butt ..and I often get it wrong by pressing the wrong button.

There’s a better solution, however. Download This utility (I refuse to call it an app) Switch Off LCD and copy it to each PC- this will allow you to disable output to your monitor from your PCs without needing a switch box. You’ll still need something to control your other cables but a KVM switch box can handle that. Something like this will do (it’s what I use).

Hopefully nobody is using PS2 mice or keyboards but if you are you can still buy switch boxes for these.
The utility is also very handy for disabling screen output for notepad devices and the like which is what I think it was originally designed for so check it out if you’re interested in this too.