Two computers, one mouse, no KVM required.

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It's relatively common for power users and those in the IT industry to have two PCs at their desk. One may be a laptop or maybe just an older machine that runs some necessary legacy software or has a lot of data on it that may be difficult and/or time-consuming to migrate to the newer system. Some use a hardware KVM (Keyboard, Video, Mouse) switch to change their screen and input device connection from system to system, while others just have a seperate set of peripherals for each machine. Each of those methods has it's own set of advantages and drawbacks, but both methods are conducive to a cluttered desktop and a nonsensically-segregated style of work.

Lately, I've taken to using a program called Synergy to share a single mouse and keyboard between the three machines on my desk.  I've been so impressed with the freedom and efficiency it allows that I was inspired to write this blog post!

Here in our repair department we use 4-way hardware KVM units. Hardware is necessary in this case because we're often troubleshooting systems at a BIOS level or running custom minimal operating systems for diagnostic purposes, and we don't have enough room for four keyboards on our benches.


Synergy is part of a growing category of applications often referred to as 'Software KVM applications', they help to alleviate some of the deficiencies of the hardware KVM and separate peripherals configurations. These applications let you use a single keyboard and mouse to control two or more networked machines, allowing you to use them in such a way that moving between systems is almost indistinguishable from moving between multiple monitors connectedto a single system. Many of them give you a shared clipboard as well. Unlike a hardware KVM switch, these applications still expect you to have a separate monitor for each system. That could also be considered an advantage since they allow the use of two (or more) monitors in ways somewhat similar to a multiple-monitor configuration on a single system, and you can keep an eye on what each system is doing without having to switch back and forth.  Software KVM applications aren't a straight replacement for a KVM switch, but I find the advantages definitely outweigh the drawbacks in many situations.

Here at Puget we use our 'monitor wall' to show the output from up to 16 individual PCs simultaneously.


Some examples of software KVM applications are Microsoft's 'Mouse without Borders', Stardock's 'Multiplicity', or the free and open-source 'Synergy'.  Here are some links to more info:

I hope you find these tools helpful – there are many options available out there even beyond what's listed above.  If you have experience with any of this software please share your thoughts in the comments.