Aucbvax.5137 fa.unix-wizards utzoo!decvax!ucbvax!unix-wizards Thu Nov 12 03:53:05 1981 Vax hardware problems >From hill@SRC-UNIX Thu Nov 12 01:49:34 1981 We have had a VAX 11/780 for about a year and have been intermittently plagued with hardware problems. The most troublesome of these problems have been a flakey writeable control store and bad power supplies. We suffered about a month of 20 minute mean up times due to the power supply problem. Fortunately, we have a reasonably capable maintenance crew here who diagnosed the problem within a week, but it took us three weeks of threats and coercion to get DEC to fix it. As it turned out some DEC wizard out in Colorado managed to find that the system was going through power fail procedures when it was telling us about bad stacks and double faults. We had DEC scope the power supplies and convinced ourselves that they were too spikey for a stable system. DEC's response was that they were switching power supplies and therefore spikes were normal. The power supplies have been replaced and we have had no problem since (about two months). Incidently, the writeable control store problem caused strange error messages also. Typically, they were machine checks during fortran program execution. Hope this helps. Alan R. Hill ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.