What does Non-Interlaced or NI mean?
In order to operate in the 1024 by 768 mode the horizontal sweep frequency has to be 768 times the vertical rate of 60 Hertz. This makes it 46,080 Hertz or sweep lines per second. This is the non-interlaced mode which requires the monitor to be more complex in design than a standard VGA which operates at 31,500 sweeps per second. In order to get around this requirement, monitor manufacturers came up with the interlaced mode where the picture is scanned slower but is painted on the screen in two passes. The net result is that an interlaced monitor will have a tendency to slightly flicker on screens with a lot of white showing like windows desktop.
