Re: Crashes with ZipGSX

[rubywand@aol.com (RUBYWAND)]

In article <19961010221143532722@dempson.actrix.gen.nz>,
dempson@actrix.gen.nz (David Empson) writes:

>....
>It appeared to be a temperature related fault, because the computer
>worked fine for several minutes after being switched on.  It then went
>through a period during it would keep crashing, but after an hour or so
>it would work reliably again.  (I think it eventually got to the point
>where it never worked reliably, but I haven't used that card for at
>least three years, so my memory is a little hazy.)
>
>> Any ideas? Could this be a power problem? I do still have the stock
power
>> supply in this computer, as well as a RamFAST, AudioAnimator, and
Quickie
>> card. I've been meaning to buy one of the Buggie power supplies. Is
this
>> the push I need?
>
>Could be.
>
>One thought that comes to mind: has your ZIP been modified to provide a
>higher voltage to the CPU?  This was done on my second ZIP (as supplied)
>but not on the first one.
>
>This modification involves several components around the "Q2"
>transistor-like device near the slot connector (at the bottom of the
>card directly under the leftmost RAM chip).  This area was unpopulated
>on my original card.
>
>This circuitry derives a supply voltage of about 5.3V from the 12V rail
>through an adjustable regulator (Q2).  The extra voltage allows the CPU
>to run more reliably at higher speeds (especially at speeds higher than
>its printed rating - my second card has a 7 MHz CPU clocked at 8 MHz).
>
>

     Quite a few GS users seem to be 'rearranging the deck chairs' without
taking a hard look at the 'ship' which is about crunch into an iceberg.

     Experiments strongly indicate that the core problem is increased
system noise combined with reduced noise immunity (mainly, sub-5V
at-motherboard operating voltages). It is too bad that the required mods--
fat +5V, GND, +12V power supply leads and leads added to Slots on the
motherboard-- are kind of messy. However, until someone repeals Ohm's Law,
greatly reduces load current, or finds some way to teleport power to Slot
boards, we a stuck with mundane stuff like wires and connectors.
      


Rubywand