Re: TransWarp & Zip GS upgrades

[CUTblakeney@home.com (Jeff Blakeney)]

On 25 Mar 2000 18:49:22 GMT, supertimer@aol.com (Supertimer) wrote:

>The newer design 14Mhz 65C816 is different because
>on the TWGS and Zip GS it is underclocked so it runs
>very comfortably at 5v at any speed.  In fact, the design
>has proven stable up to at least 20Mhz which is why
>CMD can use them in the SuperCPU accelerator at
>20Mhz all the time.  In fact, running the newer 65C816
>at higher than normal voltages is a waste of time and
>will put your entire IIGS at unnecessary risk.  That's
>why I tried so hard to get Nathan to update his FAQ
>on accelerators which recommends voltage increases.
>At the time, Nathan ignored all requests to update the
>FAQ.  I believe there are still folks out there who have
>5.5v on the 14Mhz chip for no benefit at all because of
>this.

What makes you think that increasing the voltage won't help?

If you are trying to push the processor and make it run faster, it
will try to draw more power.  If it tries drawing more current than
can be supplied then the voltage will start to decrease.  If you
increase the voltage, then the voltage decrease will only lower the
voltage to its normal level of 5V rather than something that might be
too low for the processor to continue operating.

This is the way electronics work.

Increasing the voltage can and does help depending on the processor,
the card it is on, the IIgs it is installed in and the power supply
for that machine.  Because there are so many factors involved, some
people may not need the higher voltage while others do.  Electronic
devices also have a tolerance range of voltages that they can used
with safely.  If you don't exceed that tolerance, there is little to
no danger of damaging the component.

As to generating the higher voltage, it can be quite simple to do with
a couple parts from Radio Shack and taking the +12V line down to
whatever voltage you want.  However, the best way to deal with it
would be to cut the +5V trace near the processor on your accelerator
card so that the higher voltage only goes to the processor and doesn't
affect anything else in the system.

Oh, by the way, suggesting to people that they can overclock their
current CPU is about as risky as increasing the voltage to a
processor.  By running the processor faster than it is supposed to, it
will use more power therefore run hotter (has to dissipate more heat)
and therefore "burn out" or fail faster than if it was left at its
rated speed or slightly slower.

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