4 Port DVI USB KVM Switch with Audio & USB Hub

Monitors may begin flickering when they receive a signal of insufficient quality. There are a few potential fixes available that will help to improve the signal quality in order to eliminate flickering:

• Replace Video Cables with high-quality Video Cables (e.g. upgrade DisplayPort 1.2 Cables to DisplayPort 1.4 Cables).
• Use shorter Video Cables to reduce signal attenuation.
• When possible, remove Video Adapters to use native Video Connection Types (e.g. go from VGA to VGA, or DisplayPort to DisplayPort)
• For DisplayPort Monitors, try changing the DisplayPort Version on the Monitor. For information on how to change your Monitor Settings refer to the Manual from the Monitor Manufacturer.
• Update the Drivers for the Computer’s GPU to the latest available from the Monitor Manufacturer.

Digital Visual Interface (DVI) is a video display interface that can contain different types of signaling, based on the application. DVI cables and ports are created using different connector types to identify what application they are intended to be used in. The connector types are identified by the number of pins on the DVI connector. DVI comes in the following five different connector types: 

• DVI-A (17 pin).
• DVI-D Single Link (19 pin).
• DVI-D Dual Link (25 pin).
• DVI-I Single Link (23 pin).
• DVI-I Dual Link (29 pin).

Single and Dual link DVI indicate the maximum resolution capabilities of the video source or video destination. The maximum resolutions are Single Link (1920 x 1080 @ 60Hz) and Dual Link (2560 x 1600 @ 60Hz).

Note: The maximum resolution of your video source and video destination are ultimately determined by the technical specifications of the devices. The connector type is not a definitive indicator of the maximum resolution.

DVI-A carries only analog (for example, VGA) with no digital component. DVI-D carries only digital video (for example, HDMI) with no analog component. DVI-I combines DVI-A and DVI-D connections to include both analog and digital components. A DVI-I port may be on either your video source or display, but whether or not a display carries either or both analog and digital sources depends on the technical specifications of your device.

KVM stands for Keyboard Video Mouse and KVM switches allow you to switch the use of a keyboard, display and mouse between multiple computers.  KVM switches also commonly let you switch audio and USB devices between computers.

There are different types of KVM switches as well.

• Standard box KVM switches. (e.g. SV231USB)
• Cable KVM switches. (e.g. SV211USB)
• Multi-Monitor KVM switches.  (e.g. SV231DDUSB)
• IP KVM switches. (e.g. SV841HDIE)

Standard box and cable KVM switches are a simple way to switch the use of a keyboard, display, and mouse between multiple computers.  Multi-monitor KVM switches allow you to switch multiple displays between computers, and IP KVM switches allow you to remotely control the KVM switch and connected computers over a network.

Here are some important things to consider before purchasing a KVM switch.

• How many computers do you need to control?  Purchase a KVM switch that supports the number of computers in your setup.
• Which video connections do your computers and display(s) support?  It is best practice to use the same video connections wherever possible.
• Will you be using a PS/2 or USB mouse and keyboard?
• Do you need multiple monitor support?  Ensure every computer can support the number of monitors you are looking to use in your setup.
• Do you need audio support?
• What resolution(s) do you want your display(s) running at?  The KVM switch must support the resolution(s) you want to use.
• Would you like hotkey support?  Some KVM switches support the use of hotkey combinations to complete tasks such as switching between computers.

There are a couple of other important things you may want to take note of:

• Some KVM switches require proprietary cables to function.  These KVM cables may vary by each KVM switch.  For StarTech.com KVM switches that require proprietary cables, the KVM switches will either come with these cables, or they will be listed in the Accessories tab on the individual product pages.  For more information, see our video dedicated to KVM switch cables.
• Basic mice and keyboards are recommended for use with KVM switches.  Wireless, gaming or combo mice and keyboards (mice and keyboards that use a single USB connection / receiver for both units) can cause performance issues, and in general, are not supported for use with KVM switches.

It can be difficult to tell which ones are right for the KVM switch you are interested in.  How can you tell which KVM cables you require?  How can you tell if a KVM switch requires proprietary cables?  How do these cables work? 

Standard KVM Switches and Cables

Note: You will need one bundle of KVM cables per computer you want to connect to the KVM switch.

Standard KVM switches have no special cable requirements.  If you have spare video and PS/2 or USB cables, you can use them to hook up the KVM switch to your computers.  StarTech.com still sells KVM cable packages, but they are just for the convenience of buying them in bundles and usually involve some savings.  Keep in mind that even if you have some of the cables you need, it still might be advantageous to buy the bundle.

KVM Switches with Opposite Gender Video Connections

Some KVM switches use male video connections for the computers and female video connections for the console ports.  In this case you simply need a video extension cable, or a KVM cable package appropriate to the KVM switch.  This is so you cannot accidentally plug cables from your computer into the console ports.

KVM Switches Requiring Proprietary Cables

KVM switches can also use proprietary KVM cables to connect to the individual computers.  This is often done with larger KVM switches and KVM switches intended for a server environment.  These cables use a proprietary pinout which does not conform to the video standard in use, as the cable carries both the video and PS/2 or USB data along a single cable.

If you are unsure whether or not you need special cables, complete the following:

1. Check the Technical Specifications tab on the individual product pages for What's in the Box.  This section lists everything that comes with your purchase, and your KVM switch might come with the cables.
2. Check the Accessories tab.  This section lists potential accessories for the product you are looking at.  StarTech.com will list the appropriate KVM cables for the KVM switch here. 
3. Check the Gallery and look at a picture of the back of the KVM switch.

Note: If there are no PS/2 or USB ports on the back of the KVM switch other than for the console, you will require proprietary cables.

If at this point you require further assistance in deciding which cables to purchase with your StarTech.com KVM switch, contact our technical support team.  

This device has a DVI-I connector and is compatible with both analog and digital DVI video signaling. If you have a display or video destination that uses another type of video connection, there are ways that you can convert the video signal or connection. These options are outlined below and organized by the target connection.