Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!ucsd!pacbell.com!ames!sgi!silvlis.com!jimb From: jimb@silvlis.com (Jim Budler) Newsgroups: comp.sys.mac.hardware Subject: Re: RAM for a Mac + and monitor Message-ID: <1990Sep22.031706.20431@silvlis.com> Date: 22 Sep 90 03:17:06 GMT References: <15050@burdvax.PRC.Unisys.COM> <1990Sep20.223007.24779@d.cs.okstate.edu> Sender: usenet@silvlis.com (USENET news maint) Reply-To: jimb@silvlis.com (Jim Budler) Organization: Silvar-Lisco,Inc. Sunnyvale Ca. Lines: 81 In article <1990Sep20.223007.24779@d.cs.okstate.edu> minich@d.cs.okstate.edu (Robert Minich) writes: >|>I am thinking of installing 4 Mb of RAM into my mac + but I have heard >|>that the power supply for the plus hasn't been updated since well before [...] >|>power supply. I have already had to replace my power supply once because >|>of this burnout and I am worried that 4Mb would be too much of a strain on [...] >| ------------ Clip and Save ------------ Clip and Save ------------ >| >| The power supplies on the 128K Macs were worthless; the power supplies >| on the Mac Pluses has been improved to almost marginal. I've had a >| Mac for six years and have had the power supply replaced three times >| so far; I understand this is about average. So go ahead and I have a 6 year old Mac 128 --> Mac 512 --> Mac 512ke --> MacRescue 4meg. >| For power supply burnout, you can have a brand new marginal power >| supply installed by your Apple dealer for about $145 parts, $40-80 >| labor. Or you can upgrade the power supply yourself, much more >| cheaply, and get a decent quality power supply in the bargain. Here's Probably *very* true, but maybe not necessary with a little preventative maintenance. >into the carrying handle) would do a much better job. After attatching the >Dove upgrade, I _did_ make sure the voltage coming out of the analog stuff >was within the specified range (in the upgrade instructions.) Could this be Exactly. My preventative maintenance point #1. My 128 --> 512 and 512 --> 512ke upgrades were performed by an dealer that I *know* has an extremely well qualified service staff (Computer Plus, Sunnyvale, CA) who I am confident does such checks, and who also ran burn-in memory checks after the upgrades. > If my power supply should ever die, I'd be the first to seek out a third >party kit to do it myself. But is the high failure rate of Plus analog >boards just cruddy circuit design (it must at least be partially) or lack >of circulation in the case? You bet, me too. >-- >|_ /| | Robert Minich | My preventative tip #2: The pins on the analog board into which the harness plugs are known to develop cold solder joints over time. If you know how to solder reflow all these solder joints to eliminate the cold solder joints. The pins on the CPU board for the same wiring harnes have the same potential. Do it there also. The pins connecting the flyback transformer to the analog board also. Preventative tip #3: The wiring harness connecting the analog board to the CPU board uses crimp connectors. I found these to have become loose. Use a pointed object to depress the clip holding the crimp connector in the plastic shell. Carefully remove the crimp connector and recrimp or solder it. Do this one crimp connector at a time to avoid losing the proper order. Check and fix both ends. After you put it all back together, *check the voltage again*. I had a half-volt difference between the 5 volts on the CPU board and the 5 volts on the analog board before doing this resoldering! Not after. I had an annoying *flicker* at the top of my screen before doing this. Gone now. My 2 cents. Good Luck, jim -- Jim Budler jimb@silvlis.com +1.408.991.6115 Silvar-Lisco, Inc. 703 E. Evelyn Ave. Sunnyvale, Ca. 94086