On Feb 16, 2010, at 6:34 AM, John Carmonne wrote: > I have 3 Imac G3s one 700MHz and two 600MHz. One of the iMac 600s is very > slow compared to the other two. All machines have the same systems via CCC. > The profiler specs are the same between the two 600s. I'm kinda stumped as to > what could be problem. Anyone else have this trouble?
Hi John, "Snarky Jim" here. I see that a lot on the G3 iMacs that go through my hands on the way to kids and schools. Sometimes it's a hard drive about to fail, or software that's FUBAR. But usually it's a mismatch between RAM sticks, *especially* if the iMac is running OS X. To resolve the issue, the first thing I do is to check and replace the PRAM battery, if necessary. Then I do an Open Firmware reset (set-defaults, reset-nvram, reset-all). Then I run a bad sector test on the hard drive using Disk Utility while booted to an OS 9.2.1 retail CD. If the hard drive passes -- and in my experience that's a very thorough and reliable test -- then I boot the iMac from the Apple Hardware Test disk. Before running either the Quick or the Extended test I click on the Hardware tab and compare the specs for the sticks in the two RAM slots. If the specs on the two sticks are not identical (exception: amount of RAM can vary), then I swap out sticks until I get a matched pair even if the manufacturer is different. Then I run AHT. If there's still a problem, AHT will tell you where it is. (NOTE: AHT will not run in some early G3/350 and G3/400 iMacs.) Mismatched RAM sticks in a G3 iMac, in my experience, is the cause of slow running machines above and beyond any other possibility. The difference in CL 2 and CL 3 latency specs in a mismatched pair also causes kernel panics and freezes while booted into OS X. OS 9 is more tolerant, but the problem still crops up. Getting the "right" RAM is the most important thing you can do for an iMac G3. For example, I took in a basket case last Friday. The 500 MHz iMac was missing the bottom case and the EMI shield, but otherwise was more or less complete. It wouldn't boot, and I heard a small "sizzle" noise only during the first attempt to start it. So I took out the two RAM sticks, inserted one that I knew was good from a previous Apple Hardware Test, and the iMac started, chimed and booted. HTH, Jim Scott -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/g3-5-list
