Re: ZipGS 15/64 problem was heat related!

[spec@vax2.concordia.ca (Mitchell Spector)]

In article John@klatch.demon.co.uk writes...

>I've been thinking of doing this myself for some time.
>These PC heatsink/fans cost $10 or less and have a PC style
>power connector (male/female) which you fit between another
>male/female pair.  There is usually a sticky peel-off label
>on the back so you could stick it directly to the ASIC.
>Should keep it super cool.

    Well, I tried a regular fan that was pulled from an old 
286 powersupply. It's marked "DC Brushless Model no.011388"
with a rating of "DC 12V - 0.13A" and red and black wires.
I stripped the insulator off the ends of both wires and 
attached a two-pin molex so it connected directly to the 
"fan" connector on the GS motherboard (btw, the pin closest
to the powersupply is +12 [red], the other is ground [black]).

    Unfortunately, although the fan worked and I found a nice
spot to place it without obstructing slots, it didn't fix my
ZipGS. :/ I _did_ notice a noticable improvement in stability 
(much less frequent lock-ups and more time for the problem to 
occur) but overall it wasn't enough. I probably need a stronger 
fan; again using the desk fan with the lid off makes things 100%
stable. Oh, and I tried placing the 286 powersupply fan in three 
different positions, none made a difference (blowing at an angle, 
along the length of the card and even place right up against the 
Zip ASIC). Admittedly though, the air flow it creates itsn't very 
strong, so I'll try again with another.

>Can anyone tell me if Dr. Buggie's PSU has these PC style
>connectors on them?  They would be immensely useful for 
>connecting certain items in a GS or a "Towerized GS".

    He usually keeps at least one of those molex-4 connectors
left attached, which contain a +12 and +5 voltage. I was able
to test the fan originally by sticking the red wire (+12v) 
into the yellow wire pin on that 286 supply (the yellow on
those are +12v, the red is +5v, black wires are ground).

    So yes, it should be quite simple to have the Buggie supply
(or any other PC supply with various connectors for hardrives/
floppy drives/etc) power a cooling fan. The "fan" connector on
the GS motherboard (behind slots 1 and 2) can be used as well,
it just draws it's power from whatever powersupply your IIgs 
is connected to.

Mitchell Spector
spec@vax2.concordia.ca