From: mal11@po.CWRU.Edu (Matthew A. Lewis) Subject: calculating resolutions for X Date: 6 Sep 1992 23:07:48 GMT
i'm trying to get my Xconfig file set up for my
Orchid Prodesigner IIs and NEC 4FG. Unfortunately, I've
found some troubling numbers.
According to the setting of the DIP switches on the
back of the SVGA card, the following refresh rates and resolutions
go together: 640x480 72Hz
800x600 72Hz
1024x768 70Hz
and the card is in some sort of accelerated mode.
Now.....if I calculate backwards with these numbers, I get a clock timing/
driving frequency of about 55Mhz for the 1024x768 mode.
I used the equation in video.tutorial. Now if I run
clock.exe.....I get the following numbers (i ran it several time):
detected clocks: 25.2 37.9 18.9 45.0 25.2 37.8 18.9 45.4
detected clocks: 25.2 37.9 18.9 45.0 25.2 37.8 18.9 45.3
detected clocks: 25.2 37.9 18.9 44.8 25.1 37.6 19.0 44.8
detected clocks: 25.2 37.9 18.9 45.0 25.2 37.8 18.9 45.0
detected clocks: 25.2 37.9 19.0 45.0 25.2 37.8 18.9 45.0
(BTW, do I round these????? and why????)
However, according to vga.dbase......this card should have
some high clock timings..........
vga.dbase lists25 28 32 36 40 45 75 65
Why doesn't my card read those higher frequencies??? i should read at least
have 55 cuz I have used 1024x768 under windows.
In addition....I assumed that my card did have 65 as a clock timing and
when I followed the custom setup directions in video.tutorial and
came up with the same numbers as the example, they failed to work.
The specs in my monitor docs seem to say that it is VESA compatible.
I'd really like to have 1024x768.....and not a custom mode........
but the settings in vga.dbase don't work for me. i assumed
that NEC 4d and my 4fg were similar. that might be a flaw.
Anyways.....if anyone has any ideas about thes clock timing.....or
if they have this same setup....i really like to hear from you.
I wonder if I have VCO's that don't have enough juice.......
--
MaThiEu a. LeWis "There is no middle ground/Or that's how it seems/For
Thieves Like Us us to walk or to take/Instead we tumble down/Either
mal11@po.cwru.edu side left or right/To love or to hate."
-A Strange Kind of Love