Re: Ultra 5 TFT problems

From: dick (dickdijk_at_xs4all.nl)
Date: 12/07/03 

Date: Sun, 07 Dec 2003 12:30:14 +0100

x@x.x wrote:

> In article <3fd01fec$0$206$e4fe514c@news.xs4all.nl>, ***
> <dickdijk@xs4all.nl> wrote:
>>Hi,
>>
>>I have an Ultra 5 that works OK with a Compaq 1520 TFT screen, but with a
>>different TFT screen, Medion 6155, I only get a black screen. I even don't
>>seen the system boot (black screen during OpenBoot)
>>
>>Are these TFT's so sensitive to correct input signals that the Compaq
>>accepts it but the Medion not.
>>
>>Or could there be a different problem.
>>
>
> Many resolutions that Sun uses on many of it's cards are composite sync,
> and
> not separate sync which PC commonly use. Some monitors handle both
> and some only separate sync. You may be able to set a different
> resolution in the fcode properties that has sep sync. 1280x1024x60 is
> a
> good first guess. Some older cards only have hardware for composite
> sync, however, so it still may not be possible.

How do I set the fcode properties? Do Solaris patches affect the OpenBoot
program as well?
>
>>I read somewhere that the Sun video card (PGX, m64B@2, rev 4754.9a)
>>outputs rather weak signals. Is this true and could that be the reason of
>>the black screen?
>>
>
> The "weaker" signal is the "PC" standard (2000 Ohms). Many of the cards
> listed above are OEM's from PC vendors, and have the weaker signal, but
> using
> a PC monitor should match that. They just can't drive a "real" sun
> monitor (75 Ohms) without a special "booster" cable.
>
>
>
>>Or could it have to do with the colordepth. The Ultra 5 is set to
>>1024*768@60 and 8 bits color (quite low). This resolution is suppported in
>>the Medion manual. In the manual it says "colordepth maximum 16 million,
>>but could 8 bits be too low?
>>
>
> Monitor just see the final RGB analog signals, they don't care how those
> colors were derived.
But I thought the TFT screens were digital!