Many of the Linux users I know have more than one PC, and most of the time they use them simultaneously. There are several ways to do this. The first, and most obvious, is to have one monitor, keyboard and mouse for each machine. This can be messy and difficult to manage, however. For those short on desk space or who don't want the hassle of switching input devices, there are devices, called KVM (keyboard video mouse) switches, which will run multiple computers off of one set of mouse, keyboard and monitor. Today's review talks about one such device, the Belkin Omnicube SOHO 4-Port.
When it comes to choosing a KVM, there are many options. There are some that are a manual analog switch, which simply switchs the signals from your mouse, keyboard and video to another set of cables. While these function, they aren't always the best -- there are many programs that, when faced with a lack of keyboard or mouse, will fail. The cheaper KVMs don't take this into account, and so you may run into such programs that will fail if you switch between machines.
The Belkin Omnicube, on the other hand, is an intelligent KVM. What this means is that when you switch from, say, computer No. 1 on your KVM to computer No. 3, your KVM will know that if computer No. 1 (while booting, for instance) looks for a mouse or keyboard, it should find something. This prevents the problem of bootup errors and programs having trouble operating when they think there is no mouse or keyboard.
Another excellent feature of this KVM -- also a result of the Omnicube's digital design -- is that it has a very useful hotkey feature. If you want to switch from one computer to another, you don't need to use the button on the KVM, you need only hit scroll lock twice within two seconds and then hit a number key (one through four) corresponding which PC you want to switch to, and you will be switched to that PC. This is handy because using the switch on the KVM, if you want to switch from PC 1 to PC 4, you have to hit the button three times in order to get there. By using the hotkeys, you can go directly from PC to PC.
One problem with KVM switches is that, with the extending of the VGA cable over a longer distance, signal degredation becomes a problem at high resolutions and frequencies. Running at 1024 * 768, I could not go higher than a 60Hz refresh rate without having a problem with ghosting (images would seem to be "smeared" on the monitor). Running at higher resolutions caused no trouble up to 1600 * 1200 as long as the refresh rate was low enough. For those running large monitors at high resolutions, ghosting might be a problem, because they will want a higher refresh rate. For most users, however, this should not be an issue.
Included in the package is what is needed to connect the KVM to your monitor, mouse, and keyboard, as well as a power supply. However, in order to connect the KVM to your PCs, you need to order cable kits, which can beas low as $8 a piece on sites such as Pricewatch.com. It is recommended you either buy the Belkin cables or obtain well-known high quality cables, in order to avoid signal degredation in the VGA connection.
During my use, I found the Omnicube 4-port to not only be well designed, but to be extremely useful. Where I would have had to switch cables before, I know simply hit a few keys and I am working on my other machine. While using the device to switch between a Windows machine and a machines running XFree 4.0.1, I had no problems. Other than a short pause before the mouse is workable, the device works flawlessly.
For those users who need the ability to run multiple PCs from the same station, a KVM can be an invaluable tool. While the Belkin Omnicube is a little more expensive than some KVMs, running around $100, the quality and features of it make it well worth the price. The Omnicube is a solid device from a company known for quality product, and I feel safe recommending it to those who need such a device.
Check out Belkin's Web Page.
Jeff Field is NewsForge's hardware reporter.
NewsForge editors read and respond to comments posted on our discussion page.