Thanks for all the suggestions, everyone. I've pretty much tried EVERYTHING people have mentioned, including the reseating of RAM and various connections. Actually, that was one of the first things I tried. I even tried booting WITHOUT the expansion SIMMs and just the on-board built-in 2MB RAM. Same result. And yes, these are multiple, inch+ wide bars on screen not a single vertical line.
I'm sort of at the end of the line as far as attempting to remedy this situation. I sent the motherboard through the dishwasher today as a last-ditch effort to fix things, and I'm going to let it dry for three days before testing it. If this doesn't help, I'm going to give up on this one and try to find *yet another* replacement. :( Thanks, Nat ----- Original Message ----- From: "Tom Lee" <[EMAIL PROTECTED]> To: "Compact Macs" <[EMAIL PROTECTED]> Sent: Sunday, February 22, 2004 5:32 PM Subject: Re: Mac Classic II booting trouble > The vertical stripes problem is almost always a hardware problem. If it isn't a > single, thin line straight down the middle, it is caused by a > motherboard/ram/rom problem, rather than an analog board problem, assuming that > the supply voltages are correct (always check that first!). > > The easy things to try are to reseat ram, rom and anything else that you see > that can be reseated, so you might as well do that. Perhaps that is the problem > in 5-10% of the cases, but a much more common source is leakage of chemical goo > from the many electrolytic capacitors on the logic board. The goo is conductive, > and as you might imagine, shorting together a bunch of wires at random is not a > good thing. Indiscriminate cleaning of the whole board with the dishwasher > method seems to work for a lot of folks, as crazy as it sounds. It doesn't heal > the capacitors, of course; it just cleans the goo off of the board, so there's > always a chance that additional leakage is in the cards for the future. > > Goo leakage is also responsible for other anomalies, like flaky floppy drive > operation, and various sound-related problems. In the case of very weak or no > sound, replacement of the output coupling capacitor may be required, because if > it's leaked all of its guts out, it can't capacitate any longer. :-) > > [Most of the other leaking caps are power supply bypass caps; even if a large > fraction of them fail, there are generally enough left over to allow the Classic > to continue working.] > > > -- > Prof. Thomas H. Lee > Center for Integrated Systems, CIS-205 > 420 Via Palou Mall > Stanford University > Stanford, CA 94305-4070 > http://www-smirc.stanford.edu > 650-725-3709 ph, -3383 fax > ------------ Nat Hall [EMAIL PROTECTED] ------------ -- Compact Macs is sponsored by <http://lowendmac.com/>. Support Low End Mac <http://lowendmac.com/lists/support.html> Compact Macs list info: <http://lowendmac.com/lists/compact.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/compact.macs%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
