<I might have a chance to get an old VAX-11/750 for free. I did some work
<on livingroom and now there is enough space for such a beast. But, do I
<need some external cooling? How about the air moisture level? Might soun

Not external cooling provided there is good airflow around them and a 
minimum of 2-3ft behind (for access and airflow).  NOTICE thie produce a 
lot of heat and will warm up a room greatly.

<  My VAXstation II/GPX is very picky about temperature and humidity, too
<Freshly leeched, it stopped working the other day when it was very
<hot and humid (but now works again perfectly :-)

I have two MVIIs and they seem to not mind anything up to 30c and soggy.  
I pull the plug when it gets that hot as it's uncomfortable for me and 
not good for machine reliability in the long run.

Failing at high humidity suggests there is foreign matter on the boards 
that is becomming conductive when damp.  


Allison