NetNews Usenet Archive 1992 #16/NN_1992_16.iso/spool/comp/sys/ibm/pc/hardware/20535

Text File | 1992-07-28 | 1.3 KB | 29 lines

Newsgroups: comp.sys.ibm.pc.hardware
Path: sparky!uunet!usc!sol.ctr.columbia.edu!destroyer!ubc-cs!unixg.ubc.ca!physics.ubc.ca!unruh
From: [e-mail] (William Unruh)
Subject: "flicker" and monitors
Message-ID: <[e-mail]>
Summary: flicker and color monitor
Keywords: flicker, color monotors, beats
Sender: [e-mail] (Usenet News Maintenance)
Nntp-Posting-Host: physics.ubc.ca
Organization: University of British Columbia, Vancouver, B.C., Canada
Date: Tue, 28 Jul 1992 23:16:16 GMT
Lines: 15

've been looking at some color monitors (svga) and get some wierd
effects. In particular in many stores, the white windows background
seems to flicker- at VGA, at 800X600 but not at 1000X700 interlaced.
That same monitor will not flicker in another store, or even when driven
in VGA in DOS. They are supposed to be running at 70Hz or so (bot on a
VGAWOnderXL and a Trident card) I really do not believe that it is the
refresh, since there is no way that you should be abloe to see 70Hz, and
furthermore the frequency of the intenisty variation is too low- it
seems to more like 10HZ rather than 50 or 70.
Does anyone understand this? Can you get some sort of beating between
the video refresh and the 60Hz line frequency somehow on these monitors or
on the video cards?
Bill unruh
[e-mail]