VAXstation/MicroVAX 2000 CPU/FPU overheating?

Yes, I'm wondering if it's something like that, however how likely is it that both devices would experience the same fairly-uncommon failure mode at the same time? Perhaps I've been engaging in the persuit of an undomesticated ornithoid... Is it possible that the devices normally run this hot, and the failure is occuring for another reason (possibly a side effect of the heat, as cooling them does allow it to keep running). Allison said "they do run hot" - does anyone know how hot? I did some further tests last night - I dug out my thermocouple and made some actual heat measurements with the system assembled, but with the color frame buffer removed - there should be better airflow, and this appears to be the case, since the machine did not die after 10 minites of operation. Ambient temp was measureing about 25 degrees C at the start of the test. the 70C range, then more slowly rose to temperatures of 76C for the CPU and 82C for the FPU after 10 mins. At this temperature they seemed to be getting stable - having done nearly 1-1/2 mins without an increase. It's possible/likely that they would climb anothe few degrees in extended operation. Once this temperature was reached, I held the system in RESET, and observed that the temps dropped back after a few minites to about 64C for the CPU and 68C for the FPU. To my mind, a processor running at 80C is damn hot - most of the embedded devices I work with list absolute maximum running temperature as 70C or 75C - but perhaps the DEC devices are designed to run hotter - I note the Intel 486 datasheet lists absolute maximum (under bias) as 110C ... Anyone on the list with a VS 2000 or uVAX 2000 that can do some temperature measurements? Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.classiccmp.org/dunfield/index.html