27
CHAPTER 3: Installation and Preconfiguration
3.2.3 M
ONITOR
If all of your CPUs are of the same type, we recommend that you use the
corresponding type of monitor. If your CPUs are of different types, the monitor
must be a multisync model, able to sync to every CPU’s video-output frequencies,
and compatible with all of the CPUs’ video cards.
While PC-type CPUs and VGA monitors normally use two separate leads to
send/receive sync signals (one lead for horizontal sync and one for vertical sync,
referred to as “H/V”), Mac and Sun CPUs/monitors normally send/receive a
composite sync signal on a single lead. (So do some otherwise PC-compatible
CPUs, including many SGI models.) If you attach both H/V and composite-sync
CPUs to your system, either your monitor must be capable of accepting both H/V
and composite-sync input, or you’ll have to use a sync converter and special cables
to convert H/V to composite sync or vice versa (call Black Box Technical Support
for a special quote).
For maximum compatibility, we recommend a 17" or larger, high-quality
multisync monitor capable of (a) displaying a maximum resolution of not less than
1280 x 1024 at a maximum refresh rate of not less than 75 Hz, and (b) accepting
both relevant types of sync input (H/V and composite). Such monitors are
available from many manufacturers. (However, since these monitors usually have
an HD15 video-input connector, you will need a special User Cable to use them
with Sun keyboards and mice; this cable is product code EHN059 [original] or
EHN225 [coax].) The higher the resolution you use, the less distance you can run;
see Tables 3-2 and 3-3 on the following pages.
Other concerns specific to IBM PCs:
• The ServSwitch Affinity is designed to support standard VGA video, including
VGA monochrome (“page white”). It does not support PCs that use CGA,
EGA, or proprietary versions of VGA that depart from the original
specifications. Consult your PC’s manual, and if that doesn’t tell you whether
or not the PC uses standard VGA, consult with the PC’s or the video card’s
manufacturer.
• The Affinity is also designed to support SVGA, although it doesn’t handle
higher resolutions or longer distances very well without coaxial cabling (see
the next two pages). With coaxial cables, it will also support XGA, RS/6000,
and SGI video (RS/6000 and SGI require cables with 13W3 connectors—see
Appendix B
).
If you have Mac CPUs attached, you’ll need a Mac Adapter for ServSwitch
(product code KV99MA) for each CPU that outputs video in a format other than
VGA (640 x 480).
