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Diagnostics in system profiler states that Power on Self-Test has failed. Failure type: External cache. Any idea how I can fix this?

Problem started while I was working in iMovie 6. I went to delete two large video clips that should have freed up over 10 GB of disc space. When I emptied the trash I did not get the space back. Have run the Onyx utility to clear all of the caches but to no avail. Onyx states that start up disc needs repair but I need a copy of OS X 10.5.8 to do this (Can't find my copy anywhere). Used disc utility to repair permissions. I'm still getting the fail message in diagnostics that states that the Power on Self test fails, failure type - external cache. Everything else on the machine is working fine with the excpetion of the phantom space I can't seem to retrieve. Any suggestions?


Many Thanks:


Michael

Power Mac G4 (QuickSilver 2002), Mac OS X (10.5.8)

Posted on Jan 24, 2013 10:25 AM

Reply
6 replies

Jan 24, 2013 11:09 AM in response to videoexpress

Hi Michael,


Then try a Safe Boot, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, reboot when it completes.


(Safe boot may stay on the gray radian for a long time, let it go, it's trying to repair the Hard Drive.)


If perchance you can't find your install Disc, at least try it from the Safe Boot part onward.


Another way...


Does it boot to Single User Mode, CMD+s keys at bootup, if so try...


/sbin/fsck -fy


Repeat until it shows no errors fixed.


(Space between fsck AND -fy important).


Resolve startup issues and perform disk maintenance with Disk Utility and fsck...


http://docs.info.apple.com/article.html?artnum=106214

Jan 24, 2013 1:15 PM in response to BDAqua

Hello:


Thanks for taking the time to reply. Will try option 1 tonight before leaving the office.


Not sure what you mean by machine booting to Single User Mode. I think I accessed that once on my own to get a stuck cd out of the optical drive. Machine is booting up now to my normal desktop and as I stated before, everything appears to be working fine.


Any further clarification on option 2 would be appreciated, specifically how I can access that screen to type in the command you gave me.


Again, many thanks. Will let you know how the first suggestion works out.


Sincerely:


Michael

Jan 24, 2013 1:38 PM in response to videoexpress

Single User Mode, CMD+s keys at bootup.


Should bring up the prompt to do that.


Safe mode by rights should automatially run fsck, but single user mode is slightly more informative if it can'y repair it.


I think I'd do either ASAP, running with a corrupted Directory is only going to make things worse, & can endanger more files.

Jan 25, 2013 8:10 AM in response to BDAqua

Good Morning:


I sincerely apprecite all of your advise and instructions. Just ran fsck and the last message on screen was Macintosh HD repaired. Booted machine, went to system profiler, diagnostics and it still says that the start up self test failed for external cache. Other than that, everything runs just as it always has.


Again, many thanks for your help.


Sincerely:


Michael

Diagnostics in system profiler states that Power on Self-Test has failed. Failure type: External cache. Any idea how I can fix this?

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