>pic of card cage fan installed

  <http://www.lisa2.com/XLerator.html>

(Thanks for the pics Rick!)

Although the added card cage fan is in a position that will cool the memory
boards, AFAIK they do not require anything more than convection cooling.

The primary purpose of the card cage fan is to cool the XLerator. It was
required for the original 16 MHz XLerator and the XLerator 18. It is not
usually required for the XLerator 12.5, but if the ambient temperature is
high it would be a good idea.

>All of this leads me to believe that it is prudent to have forced cooling
>(a fan) with the Lisa, contrary to what I've read elsewhere

I believe that nearly any electronic device that runs hot will last longer
with additional cooling. My rule of thumb is that any part that is "too hot
to hold your finger on" needs more cooling. That threshold is about 50
degrees celcius and seems to be fairly consistent from person to person.

As Ray said, the power supply seems to be the most vulnerable item in the
Lisa, so I try to always have a fan cooling it.

Since the cooling effect of moving air is in proportion to the square of
the velocity (IIRC), even a very gentle (and thus quiet) airflow makes a
big difference in temperature for something that was originally convection
cooled.

I see that this thread has gone way off subject, so I have changed the
subject line to make the archives more useful.

HTH,

James