9370 is a dog! Was: Re: Re[2]: Firsts - test-drb@ccmp.vtda.org

23 Feb 1998

William Donzelli quoted me as having written:

...
   All 3090
models are indeed water machines.  The 3090 was IBM's large 
 mainframe of the late 1980s. 
 Are you sure that there were not a few air cooled models towards the end? 
 I have an air-TCM from, I believe, a late 3090. I paid two bucks for it. 
 In hindsight, I should have purchased all of them in the chassis (25 or 
 16, I do not remember offhand. 
OK.  To be strictly accurate, all 3090 models of which I am aware are 
water cooled machines.  I was a student when I worked at IBM - a year 
before going to university, and two summer vacations - after which I 
somewhat lost touch with them.  My last job with IBM was in 1988, and 
not at the marketing location where I had worked before, but in a 
factory building cash dispensers.  My last real knowledge of IBM was 
...
 from 1987, then. 
...
   involved!) to
replace the strange 400Hz thingies.  And a little circuit 
 to provide a 400Hz heartbeat if the machine uses this at all... 
 This is probably the best solution.

 It probably does monitor the 400 Hz, and machine check if it goes away. 
 Remember, these machine monitor EVERYTHING (like the earthquake sensor in 
 some of them - give them a good kick and they will report a seismic 
 check).  
Ouch!  But you may get away with providing a fake "ac good" signal, 
rather than ac for it to monitor.

...
  The "Mill" was chopped up into smaller rooms
- our room just happens not 
 to have mice power, but the one next door does. 
Strange - I shouldn't have thought it took much to power a mouse :-)

Still, this means you shouldn't have much difficulty with the upgrade.

Philip.