Specifications

APPENDIX: Cable Guidelines

Appendix: Cable Guidelines

IMPORTANT NOTE

The maximum supported cable lengths vary widely between devices and

cables. It might be possible to use cables that are longer than those

specified in this Appendix with certain computers and peripherals, but

this can’t be guaranteed. If you have problems, try using shorter cables.

A.1 Cabling from the Keyboard, Mouse, and Monitors to the Multi-Head

ServSwitch

All of the shared devices plug directly into the relevant ports at the rear of the

Multi-Head ServSwitch. If you use a PC/AT style keyboard you’ll need a PC/AT

(5-pin DIN female) to PS/2 (6-pin mini-DIN male) adapter. (These are available

from Black Box as product code FA211.)

If you’re not using the optional power supply, these peripherals’ cables should be

no longer than 6 ft. (2 m). If you are using the power supply, you can use Premium

KVM User Cables (product code EHN409) to increase the distance from the Switch

to your peripherals to as much as 32 ft. (10 m); see Section 3.3.3. Many keyboards

and mice will operate at distances up to 65 ft. (20 m), but don’t count on this.

A.2 Cabling from the Multi-Head ServSwitch to the CPUs

Video cabling: HD15 male to HD15 male, wired as a standard VGA CPU-to-

monitor cable. There are two types commonly available. The better type, which will

carry video very well, is constructed with a coaxial cable core. The not-so-good

type—cheaper cable more suited for data communication—is often used, but can

degrade video quality, especially over longer distances. Avoid using “data cables”

longer than 6 ft. (2 m) unless video quality is not important in your application.

If you are not using the Switch’s optional power supply, the video-extension cable

should be no longer than 16 ft. (5 m) in any situation. If you are using the power

supply, you might be able to run good coaxial video cables as far as 165 ft. (50 m)

with little loss of video quality, but the longest we recommend going—unless you

use a ServSwitch brand KVM Extender—is 100 ft. (30 m) over the video strand of

our Premium KVM CPU Cables (EHN408; see Section 3.3.3) and/or VGA-

extension cables (EVNPS05-MM).

If you want to make use of the Multi-Head ServSwitch’s ability to pass Display

Data Channel (DDC) information between your CPUs and your monitors, you’ll

need a cable that carries the DDC signaling lines (HD15 pins 12 and 15), which

not all video cables do.