I only have experience with one (and it works fine), so I won't make a specific recommendation. However, I'll point out some features to watch for.
1. 2 ports vs more: if you can tolerate the cost difference, having more ports (like 4) is nice for future unknown situations. I have a 4-port and use it on only 2 machines mostly. But I have hooked up a third infrequently, like when I'm testing out another machine, or bring home a laptop from work.
2. Power Supply: some units use only power from the USB (or PS2) bus. But that usually means particularly the USB connection from the #1 machine, so it MUST be turned on for the switch to work. Some come with an external power input connector, but few actually include the "power brick" required. Mine had connector and no brick, but the manual specified what power (volts / amps / polarity) was required. I simply took it to an electronics shop and bought a suitable brick and the right cable-end connector to fit the socket on the switch. The shop even saved me some effort by soldering the connector onto the end of the power brick cable and checking polarity to be sure before I left. This way the switch, with its own independent power supply, ALWAYS works no matter what is turned on, and never uses power from the USB connectors.
3. "Monitor not necessary ...": most of these run cables out from switch to computers that look like VGA cables at the switch end, and have both VGA and 2 x USB (or 2 x PS2) connectors at the computer end. So whether you want to use the VGA switch or not, the cables will be there anyway.
4. What to switch: the usual units switch Keyboard, Video and Mouse together. Some add extra connections and switching for audio in and out, and occasionally I wish I had bought that, too. However, even those that do usually treat audio as 2-channel stereo only - there's nothing simple that switches 5.1 surround sound signals on 3 cables in addition to the KVM stuff.
5. How to switch: It's always handy to have a physical push-button on the KVM switch body itself to switch it, rather than relying totally on hot keys. And indicator lights to tell you which computer is active help. Hot keys are very useful, and are done in two ways. The simplest does NOT require software mounted in each computer, although some require this OR provide this in addition to the other. The simplest one, though, is all done by the KVM switch itself. It monitors the keyboard and responds to a very specific sequence to intiate switching without passing the keypresses to the computer. On mine, a double press of "Scroll Lock", followed by a numeric key (1, 2, 3, or 4) makes it switch to computer # (key pressed).
6. Auto Switch: some have a scanning feature (I don't use it) you can set in motion. It will scan through all the currently active computers in sequence, showing views of them in turn, until you intervene and choose one machine to use.
7. Video Resolution: make sure the switch can handle all the video display modes you plan to use and pass them on to the monitor correctly. In some cases I have seen reviews that complain about poor signal quality. This is especially true with high resolutions.
8. Status Restore: a handy feature, this means that the KVM switch remembers the keyboard status (Caps Lock, Num Lock, etc) and probably the video signal type for each computer. So when you switch to Computer No. x, your keyboard, mouse, etc all are reset to however they were the last time you were using x, even if the other computer(s) had different settings.
9. Connectors: Some, like me, have mixed machines or peripherals with USB and PS2 connectors. It is relatively easy to get adapters that "convert" one type to another. It turns out there is no signal changing necessary - it is simply a matter of connecting the right pin on one to the right pin on another, because the electrical signals are the same. So, for example, in my case I decided to get a PS2-based KVM unit and use PS2 connections between it and all the computers - most current machines have these connectors for both keyboard and mouse. And I simply don't bother asking the BIOS in each machine to provide "Legacy USB Support" for DOS applications. Connected to the switch I am using a keybard that actually has a PS2 connector, and a Logitec USB mouse with a small adapter to convert it to a PS2 input on the switch.
Facebook
Twitter