View Full Version : Data file corruption, apps quitting, kernal panics - Oh, My!

09-14-2003, 06:00 AM
I'm suffering some weird problems and would like some suggestions on solutions. The problems include data file corruption, app's quitting and kernal panics.
<LI>I have a PowerMac G4/400 Gigabit Ethernet with 768MB RAM and running OSX 10.2.6.
<LI>There are two 80GB hard drives: a few-year-old 5400 RPM Maxtor and a new 7200 RPM Western Digital.
<LI>The internal DVD-ROM drive is original.
<LI>I have added a 2-port USB 2.0 card
<LI>Replaced the video with a GeForce 3MX card - a PC card reflashed with Mac firmware.
<LI>I have removed virtually all 3rd party system "modifiers" (ie PrefPanes, etc).
Here are some of my symptoms:

<LI>Downloading files from USENET results in 30-50% of them being corrupt. Re-downloading the files results in the same level of corruption.

<LI>Downloading files via HTTP results in many of them being corrupt.
Re-downloading the files results in the same level of corruption.

<LI>Repeatedly running corruption-detecting software on the downloaded files results in slightly different results each time (ie, a previously good file may suddenly appear as corrupt and vice versa).

<LI>Expanding .sit, .zip, and .tar files can result in corruptions in the de-compressed archive.

The above have been happening for several weeks. Repeating the exact same downloads and corruption detection from my Powerbook running OSX 10.2.6 results in virtually 100% clean files.

<LI>Copying a good, working disk image (.dmg) via ethernet from the Powerbook to the PowerMac results in a .dmg that will no longer pass check-summing and verification.

<LI>Apps frequently quit at random. Restarting the app may or may not succeed (ie, it may quit again on start-up). If successful, it probably will quit soon after. Safari quits an awful lot. Trying to run IE after a Safari quit may not succeed.

<LI>Finder suddenly quits. It may quit spontaneously or it may quit as a result of some activity in the Finder. There are two versions of this:

1) All of the Desktop and the open windows disappear, but the Dock remains. The Finder starts up and everything continues functioning as if nothing had happened.

2) Everything on the Desktop disappears including the Dock. When the Finder and Dock reappear, it is as if I had just logged in - no apps are running and my "start-up" apps are starting-up.

<LI>Apps may freeze with a spinning beach ball. Finder is locked up and cannot Force Quit. Must manually reboot.

<LI>Was experimenting with copies of Panther on another partition. Had no problem installing early betas. Most of recent betas (3 of them so far) will install through 98% of the 2nd Base installation. Then the installer will declare that there has been an error and that the installation should be re-attempted. Is it detecting "the" problem with my system?

<LI>Decided to try reinstalling OSX 10.2.6 to see if that would clear up some problems. Took approximately 6 different attempts because of frozen installs, hung re-boots for 2nd disk or corrupted installation.

I have zapped PRAM, done the Open Firmware fix, pressed the PMU switch, Disk Warrior'd the partitions, removed a suspect RAM DIMM, unplugged all USB devices except mouse/keyboard and reinstalled OSX.

Power supply fluctuations? Bad battery? More bad RAM? Flakey hard drive? Bad mo-bo or chip? The data file corruptions are especially confusing and distressing.

Any suggestions?

[This message was edited by rammjet on Sun September 14, 2003 PT at 11:27.]

09-17-2003, 05:59 AM
Seems that the problem is isolated to a single stick of RAM causing a lot of grief.

09-17-2003, 08:19 AM

?Glad you got 'er figured out. I read your post a couple of days ago but didn't have the time to pursue it then, my apologies. Turns out you didn't need any help anyway http://forums.macgurus.com/infopop/emoticons/icon_biggrin.gif We try to be a little more helpful, heck, we usually try to at least be present.

?Bad RAM is consistently the data corruption king. At least these days the cost is low enough that it doesn't break the bank to replace a stick.


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