PC speed was Re: 8' DSDD disk

Tony Duell ard at p850ug1.demon.co.uk
Mon Jun 6 17:38:32 CDT 2005

> Part of my original point about using 4.77Mhz is that all of the CGA cards I 
> ever saw had their own crystals and ignored the MB clock.

Just checked the IBM CGA scheamtics, there is no crystal shown. I've also 
just pulled a couple of genuine IBM CGA cards out of my spares box, I 
can't see anything that I think is a crystal on them. Ditto for a close 
clone of the CGA card that I've just looked at.


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