WDC -14 Problems with ZipGs Upgrade

["Marvin Miller" <marvinmiller@hotmail.com>]

Arghhhhh.......!

I'm having some difficulties with upgrading my ZipGs.

The stock card has a 28Mhz Osciallator and a -7 WDC chip with 32K.

The card has been modified and changed over to 64K using new .300 Memory
Chips
The 74F00 chip has been replaced with a 74HC00.
With the stock Oscillator (28Mhz) and the stock WDC Chip (-7) it works well
@ 7Mhz.
The card is rock-solid and was also checked over by SSH in Germany - all is
well - clean bill of health
in this modification.

When I replace the WDC -7 chip with the new WDC -14 chip the card no longer
works.
This is the only change - and the computer boots and shows the Rom 03 screen
etc. Usually there is
also a flashing cursor or some other wierdness and than the computer stops
booting.

If I replace the -14 with the old -7 it works beautifully. If I put the -14
back in, it stops working.

I suspected I had a bad -14 chip so I got another one. It too does the same
thing.

What is happening here? The only change I cannot make is putting the stock
74F00 chip back in as I don't have one.

Can somebody give me a heads-up?

PS> The computer's power supply leads have been changed over to 12 guage and
work well.

Best;.
Marvin