Re: IIGS Acceleration Idea

Bryan Parkoff wrote:
> I have to say -- do 1 GHz (GigaHertz) crystal osc chip exist?

Possibly, but it wouldn't have a 3.3V or 5V CMOS logic compatible output.
Chips that internally run over 200 MHz use an internal PLL to multiply
a lower-frequency external clock.

> If so, you will have to redesign Apple //e or Apple IIgs motherboard.
> 65816 CPU will run at 1 GHz.

Not bloody likely. You'd be very lucky to get reliable 50 MHz operation
out of those.

And even if you could run it a 1 GHz, you can't get memory suitable for
use as a cache at that speed.

If you designed your own chip in a 90nm process, you could perhaps make
a 500 MHz 65816 with some on-chip cache. You could expect to spend over
$500K on NRE. If you were able to sell 1000 chips, you'd probably have
to sell them for about $750 each to break even.

> Michael Mahon and other folks said that it is impossible,

And they're correct. You'd not just have to design your own processor,
but your own memory controller, and an interface to the "legacy" Apple II
hardware. This isn't something you can do by minor modifications to
your existing Apple IIgs logic board.

If you disagree with Mr. Mahon and want to prove him wrong, the way to
do it isn't by making up wild claims, but rather by actually doing what
is claimed to be impossible.

> I wish that it would WORK when you reinvent Apple IIgs' design of
> motherboard. If it does work, I can say that it is faster than Pentium IV
> 2-4 GHz.

No, a 1 GHz or even 2 GHz 65816 would NOT be faster than a 2 GHz Pentium 4.
.

Relevant Pages

  • Re: The problem with Macs ....
    ... would actually push the DIP chips out of their sockets. ... OTOH, the Apple IIgs was rather good, Until the Mac II came out in 1987 you couldn't do anything much with Macs that required expansion slots, so the IIgs still filled a valuable niche. ...
    (uk.comp.sys.mac)
  • Re: The problem with Macs ....
    ... Stimpy wrote: ... Apple IIGS anyone? ... I think you're thinking of the Apple III (lift it off the desk and drop it to re-seat the chips)? ...
    (uk.comp.sys.mac)