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RBR
07-16-2009, 11:58 AM
I have a dual 1.42 GHz MDD G4 which appears to be experiencing some problems with either losing or corrupting the PRAM. When starting the Mac the date/time needs to be reset, the Airport network setting loses the password, and there have been some sleep issues.

I have done a PMU reset which seemed to help with the sleep issues, but they seem to be creeping back up after a few days. I have also manually zapped the PRAM. I checked the voltage of the PRAM battery and it read 3.68 volts, which I think is within normal tolerances for the 3.6 volt battery. The battery is less than 2 years old, but I have a replacement on order anyway.

Any ideas on why the Mac would keep dropping out like this?

Thanks in advance,

Rick

M.Brane
07-16-2009, 12:20 PM
Checking the voltage on a PRAM battery is not really a good test of it's health. You really need a way to load test it, but it's probably easier to just replace it.

Nicolas
07-16-2009, 03:39 PM
I 2nd that

RBR
07-16-2009, 03:53 PM
Things went downhill very rapidly. Unable to wake from sleep at all among other niceties.

I "robbed" another machine that uses the same battery, installed it, and zapped the PRAM on startup for good measure. I have done a few restarts and the date/time and Airport settings are good on the startup (after I reset them all with the swapped out battery).

When I removed the old battery it was quite warm (it is in a MDD) which can not have been good for its useful life.

Anyway, things look good for the moment.

Thanks for the responses,

Rick

Nicolas
07-16-2009, 05:21 PM
In open Firmware (holding "ALT+APPLE+o+f" at boot):

reset-nvram (Return)
set-defaults (Return)
reset-all (Return, the Mac should restart)This should fix bad PRAM entries and should restore normal funktion also fan management.

Regards

Nicolas

RBR
07-16-2009, 07:09 PM
Nicolas,

That is a very good point. I was wondering about it but had not had a chance to try it. I will.

Cheers!

Rick

RBR
07-16-2009, 08:04 PM
I went ahead and reset the NVRAM and had a chance to try to intentionally sleep the Mac. It did not really go to sleep (based on fan sounds & etc) and definitely would not respond/wake up so I am going to have to think this over some more.

M.Brane
07-16-2009, 09:46 PM
I never use sleep. I run ProTools, and it's always been recommended by Digidesign to disable it. There's plenty of other 3rd party hardware that doesn't like it either. It causes more trouble than it's worth IMHO.

Nicolas
07-17-2009, 09:15 AM
Some 3rd Party AGP/PCI cards (ATTO UL3/UL4 SCSI, some FW/USB cards, maybe your 9800pro?) prevent the sleep or wake from sleep to work propperly.

Regards

Nicolas