[comp.sys.zenith] Zenith 33 mhz .vs. TARGA 32

bierma@nprdc.navy.mil (Larry Bierma) (03/28/90)

I have a Zenith Z-386/33 system in which I am trying to run an AT&T
TARGA 32 video/graphics board.  The TARGA board doesn't seem to
like to bus.  The people at the AT&T Truevision group say that
the Zenith's bus is too fast (66.67 clock divided by 8 = 8.33 mhz,
the targa 32 maxes out at 8.1 (if hardware is tuned)).  AT&T's
suggestion is to buy a 25 mhz machine of buy a new AT&T VISTA
board which will work on the faster bus (both cost money which
I can't get).  Is there a way to slow down the bus speed on the
Zenith system without affecting CPU performance (too much).  I
can get things to work if I use the "machine speed slow" command
which inserts 15 wait states per instruction (inserting 10 wait
states does not work).  Of course then the system is no faster
than the 8 mhz AT it replaced.

Is there any way to slow down the bus? (No straps or switches exist
on the motherboard)

--Larry		ARPA: bierma@nprdc.navy.mil
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