mischel@cunixa.cc.columbia.edu (Walter Mischel) (01/07/90)
I hope there still are people who run, or remember, sun-2. We have one of these venerable ones which has recently developed some intermittent hickups (parity error -- core dump -- reboot). Luckily the machine was on sun "mail in" service contract, so we promptly got a new CPU board from sun. However, the new one doesn't work! The LED self-test indicator on the board shows that the board is ok (4th LED slowly flashing). But the console gets no output (normally, it puts a sun logo, identifies the PROM revision #, serial #, ethernet address etc. before it goes on to load UNIX -- but none of that appears). Then I put in the PROM's from the old CPU board (which had intermittent problems) into the new CPU board, and suddenly system began to work. The sun engineer I talked to on the phone found a sentence in his service manual which said that when there is a type mismatch between the PROM's and the cpu board, video output will be disrupted. But it didn't explain further. Has anyone experienced anything like this? How does one find out if a particular PROM matches of a particular cpu board? What is the relevant characteristics of the PROM and the cpu board (revision #? multibus vs. multibus prime? 128K version of PROM vs 256K verson?)? I want to find this out because the current combination (new cpu board, old PROM) still has intermittent problems, only with higher frequency (once or twice a day!). So I want to get a replacement cpu board from sun. But since even they don't seem to know how to tell exactly what PROM works with what CPU board, I'm turning to the collective wisdom of the net. Otherwise, there is a shot-in-the-dark quality in continuing to swap just in hope to come upon the right combination. (Also is there such a things as cpu board - video board matching problem?) Any clues, hints, suggestions, and rumors are welcome. Thanks! Yuichi Shoda yuichi@luna.psych.columbia.edu 406 Schermerhorn Hall, Columbia Univ. NYC, NY 10027 212-854-8450