Re: Zip GS question

[supertimer@aol.com (Supertimer)]

Geraldine.A.Wright.1@gsfc.nasa.gov (Geraldine Wright) wrote:

>Is the Zip GS a power hog? I recently installed one, and my gs now is 
>balky about booting. I have ordered a Buggie power supply, but would be 
>interested in hearing of other possible explanations for the annoying 
>behavior.

The Zip GS is not a power hog.  It sips power.  The TWGS is more
of a power hog (it is the card I have) but even it is not too bad if you
have cooling for your system.  Certainly nothing compared to how
a typical Pentium or compatible hogs power.

Possible causes for problems:  the CPU is the main suspect.

Usually this affects TWGS cards because they were manufactured
first.  The dirty little secret is that the early 65C816 design had
speed problems.  In an older accelerator, the 65C816 can be
considered overclocked.  As with overclocking a processor on a
PC, this affects the lifespan of the chip.  Not suprisingly, many
TWGS cards no longer work.  As time passes, this phenomenon
may come to affect more and more Zip GS cards.  Besides, even
without design flaws, processors may start to fail in 10 years through
normal decay (at least that's what they say about PC processors).

The good news:  Western Design Center contracted Sanyo to
completely redesign the chip, shrinking the die and improving
the design reliability of the chip.  This time, they've outdone
themselves.  The newer 65C816 chips are so good that they can't
be tested to their full potential on WDC's testing equipment, which
max out at 14Mhz.  In fact, CMD MicroDevices had WDC's go
ahead to clock the chips at 20Mhz.  They used an outside lab
to test the chips at that speed.  Not a single one failed in the CMD
accelerators' production run.

Basically, the newer 65C816 units are grossly UNDERclocked
at 14Mhz.  Now the TWGS and Zip GS cards' OTHER
components limit the speed of the cards to around 15Mhz or
16Mhz.  Thus, the newer 65C816 is ALWAYS effectively
underclocked for its design when used on a TWGS or Zip GS.

My recommendation is to buy a new 14Mhz 65C816 unit from
them and upgrade the speed of your Zip GS at the same time.
Not only will you enhance your IIGS, but you will be replacing
a questionable part with a reliable one.  They only cost around
$20 to $25 each.