Xref: utzoo unix-pc.general:3785 comp.sys.att:7668 Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!rutgers!att!icus!limbic!gil From: gil@limbic.UUCP (Gil Kloepfer Jr.) Newsgroups: unix-pc.general,comp.sys.att Subject: Re: sick disk?! Summary: Get the disk of the motherboard Message-ID: <569@limbic.UUCP> Date: 28 Sep 89 01:54:41 GMT References:<3454@cbnewsc.ATT.COM> Reply-To: gil@limbic.UUCP (Gil Kloepfer Jr.) Distribution: na Organization: ICUS Software Systems, Islip, NY Lines: 40 In article <3454@cbnewsc.ATT.COM> psfales@cbnewsc.ATT.COM (Peter Fales) writes: >and checked the power supply voltages. Ah ha! Power was going up and >down randomly between about 4.5 and 4.8 volts. Then I happened to look >at the connector where the cable from the mother board connects to the >power supply. Pins on this connector alternate with odds pins as +5 and >even pins as ground (or vice versa, I don't remember). In any case, the >plastic connector was discolored near each of the five volt connectors, as >if those pins had somehow gotten very hot! When I pulled the connector >off the pins on the power supply were black (like smoke). >UUCP: ...att!peter.fales Naperville, IL 60566 My last inspection of the power connector on my UNIX-pc seems to have the same problem, although my system has been working BETTER than normal since I got it over a year ago. I think that polishing the connector will probably improve the problem. One thing to those with 7300s that have upgraded their machines to 3B1s, or to those with perhaps braindamaged 3B1s, where the hard drive is powered from a spot on the MOTHERBOARD -- fix this. If you're handy with a soldering iron and have a multimeter handy, solder a new 4-pin molex connector with relatively thick wires onto the power supply directly. 3B1s usually have this done in the factory. The reason is that the motherboard power supply cable is responsible for powering all the expansion boards, the video display, and the floppy drive! This is a LOT of power, and that power supply line to the motherboard is cheap. My apologies if this procedure is impossible because it just can't be done -- I don't own a 7300 so I have only a small idea how to proceed and where to hook the wires on the power supply (maybe someone out there can supply this information, no pun intended). In any event, this will help preserve the life of the power supply connector. If worse comes to worse, this connector can (with great effort) be removed and replaced with one of those heavy-duty Molex-type connectors, but I wouldn't do it unless you're REALLY having a problem with it. ----- | Gil Kloepfer, Jr. | ICUS Software Systems/Bowne Management Systems (depending on where I am) | ...ames!limbic!gil or gil@icus.islp.ny.us