CGA & clock speeds

From: ACC student <defaultuser_at_mail.mankato.msus.edu>
Date: Sun Nov 23 17:22:28 1997

Hello,

I hope this mail goes to the right place as I'm not on the list; here
goes:

I am messing about with an 8088-based clone to see what I can do with it

for cheap thrills & a good learning experience. So far, I have
installed
a V20 chip which decreased processing time by about 7%. I then tried to

clock it at 10 MHz (the rating of the chip), but this failed to produce
any results (the 'puter did not boot.) I tried at 8MHz, and the
computer
booted but did not give a display. I could tell it was working by
entering
DOS commands. I tried then at 5.33 MHz. It booted & ran OK (as far as
I
could tell), but the display was all messed up. I then did some
research
and found that the CGA card depends on the 14.31818 oscilator to run
properly.
Since the processor seemed to be running OK at 8 MHz, what I want to do
is
find a way to send a proper clock signal to the CGA card while clocking
the
main board at 8MHz. Or will changing to a different monitor (like VGA)
make the clock speed irrelevant? Is CGA the only clock-dependant
display
type?


Thanks in advance,

Dave
Received on Sun Nov 23 1997 - 17:22:28 GMT