40
SERVSWITCH™ ULTRA
By contrast, coaxial cables (standard for Sun applications, required for XGA
applications, and recommended for most other applications) do much better at
maintaining video quality, as shown in Table 4-3 below. (For the meaning of
quality numbers
3
,
2
, and
1
, see the bottom of page 39.) As before, the distances in
the table are total cable lengths measured from the CPU to the monitor. Also as
before, the table assumes a single ServSwitch Ultra is between the CPU and
monitor; if there is a submaster as well, video quality will always be lower. (Where
“interlaced” or “noninterlaced” isn’t specified, noninterlaced video is implied.)
Table 4-3. Video Quality vs. Distance for Coaxial Cables
Resolution
Distance
10 ft.
20 ft.
30 ft.
50 ft.
75 ft.
100 ft.
150 ft.
200 ft.
(3 m) (6.1 m) (9.1 m) (15.2 m) (22.9 m) (30.5 m) (45.7 m) (61 m)
640 x 480
3
3
3
3
3
3
2
2
800 x 600
3
3
3
3
3
3
2
2
1024 x 768 interlaced
3
3
3
3
3
3
2
2
1024 x 768 noninterl.
3
3
3
3
2
2
2
1
1280 x 1024 interlaced
3
2
2
2
2
1
1
1
1280 x 1024 noninterl.
3
2
2
1
1
1
1
1
1600 x 1280
3
2
2
1
1
1
1
1
CAUTION!
Some CPUs can’t drive or receive keyboard and mouse signals across
longer runs of coaxial cable. Consult with the manufacturers of your
CPUs before installing this cable in lengths greater than 20 ft. (6.1 m).
For CPU-to-monitor distances over 200 feet (61 m) in IBM PC applications, Station
Extenders or CAT5 KVM Extenders might be required. Call Black Box for
technical support to discuss this option.