On Sun, 21 Apr 2002, Leonard Sitongia wrote:

> I'm trying to get my laptop to display on both the LCD and an external CRT.
>
> Often the setting will cause the LCD to start rapidly brightening, with it
> appearing to burn in.  I don't know what to call this.  It looks bad, so I
> immediately power it off (ctrl-alt-backspace doesn't kill it, so X probably
> isn't running far enough along to do that).
>
> What causes this?  Is it really as bad as it seems?  :-)
>
> I'm tempted to hypothesize that this is caused by driving the LCD at a higher
> res/rate than it supports, but it's not clearly the case, because I can
> sometimes get it to work (it=driving the CRT at a higher res than the LCD),
> but it seems to depend on whether the LCD and CRT are both initially on (via
> Fn-F8).

In my experience (#9 Ticket To Ride IV, Permedia-3 1600SW, SGI 1600SW),
the incorrect polarity of the hsync and/or vsync causes the *exact*
effect you mention.  In my case, it had _nothing_ to do with the rate
at which the LCD was being driven.

That said, LCDs can be fried, and your case may be different.  I
didn't wait to see how a prolonged exposure to this effect affected
the LCD. :-)
Ctrl-Alt-Backspace always killed the X server and cleared the
effect.



========================================================================
 Nikola Miljanic [Nick] |                    | Metro Link, Inc.
 [EMAIL PROTECTED]     |                    | http://www.metrolink.com
========================================================================
progress [n.] 1. In computing; advancing from one error message to the next


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