InFocus SP4800 User Manual page 22

Problem
no computer image, just the words "Signal out of
range"
Solution
press the Auto Image button on keypad
adjust computer refresh rate in Control
Panel>Display>Settings>Advanced>Adapter
(location varies by operating system)
you may also need to set a different
resolution on your computer, as shown
in the following problem, "image fuzzy
or cropped"
21
Result
computer image projected