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3andahalfeyed · Dec 10, 2005, 05:04 AM

Hi There!

First I'll say I am new to the boards. Been using Macs since about 6th grade with the old Mac SE and Mac SE/30 in schools. But really cranked up Mac knowledge with an iMac (Lime-colored 333 Mhz).

Currently I have a MDD G4 1GHzx2. And I have some questions. But I'll start with this one only.

We get many power failures in my town. Well in my grid, we probably have the weakest grid in the city.

And when I turn the machine back on. The computer is partying like it's 1969. Around December or so.

I want to know if this is actually normal after power failures? I am actually still stuck using Jaguar right now (10.2.8), and probably might move to Tiger to finish off this 3 year old box.

I don't know if it is an OS problem so that is why I put it in this category. Because I am thinking it may also be a HW problem; ie, PRAM.

I kind of need info here.

SoBayJake · Dec 10, 2005, 06:15 AM

Sounds like your clock battery is dead. You can check apple.com for information on how to change it.

Or if your computer is on the net all the time, it will correct the time itself. Its not the best solution, but doable until you get the battery replaced.

Try here: http://docs.info.apple.com/article.html?artnum=26259

-J

NeilCharter · Dec 10, 2005, 01:16 PM

Yup it is the clock battery alright. You may also lose other settings such as PRAM etc. Definitely should replace it ASAP as it can cause other problems. Check OtherWorldComputing or other vendors for a replacement. Usually around 10 bucks.

I would definitely recommend moving to Tiger. Your Mac will perform better with it compared to Jaguar.

3andahalfeyed · Dec 15, 2005, 03:09 AM

Thanks for the info there. Now is this battery the same that is next to the AGP slot? I would think it is since it is the only one I have seen, unless some other one is hidden in the tower.

Second - This has only been happening after a power outage of any sort, and not by other methods of shutting down.

My guess it may also happen if I didn't shut down properly; ie. pressing the power button.

But the clock doesn't reset when I have to perform a hard restart by holding the power button for several seconds.

SMacTech · Dec 15, 2005, 12:54 PM

Originally Posted by NeilCharter

Check OtherWorldComputing or other vendors for a replacement. Usually around 10 bucks.

Radio Shack carries these batteries in most all of their stores.

Detrius · Dec 16, 2005, 03:47 AM

Originally Posted by 3andahalfeyed

Thanks for the info there. Now is this battery the same that is next to the AGP slot? I would think it is since it is the only one I have seen, unless some other one is hidden in the tower.

Second - This has only been happening after a power outage of any sort, and not by other methods of shutting down.

My guess it may also happen if I didn't shut down properly; ie. pressing the power button.

But the clock doesn't reset when I have to perform a hard restart by holding the power button for several seconds.

The issue isn't a matter of how you shut the machine down--it's a matter of whether or not the logic board loses power. If the Power Management Unit either loses all power or crashes, then the clock will be wrong the next time you start the machine up. If the battery is dead, then if you unplug the computer from the wall, your clock will be reset (regardless of whether its on or off--but you really should shut down first).

One important detail to note, though: Many many times, I have seen the PMU crashed because the power went out while a machine is asleep. The symptom is that the machine will no longer start up--no chime, nothing on the screen, etc... The power button lights up when you press it, though (assuming the button lights up at all).

Just some details...

angelmb · Dec 16, 2005, 02:20 PM

Originally Posted by 3andahalfeyed

We get many power failures in my town. Well in my grid, we probably have the weakest grid in the city.

I would buy a UPS device. So you can shut down the MDD properly, save documents you are working on, send that huge mail completely and so…

P · Dec 17, 2005, 10:28 AM

Originally Posted by SMacTech

Radio Shack carries these batteries in most all of their stores.

Photo shops do too, sometimes. It's a 3.6 V Lithium battery.

The reason it only loses the clock after a power failure is that the Mac uses a little power (some 2W or so for mine, may vary - newer machines keep more features on standby even when the power is off) even when turned off to keep power to the PRAM and the clock chip. Only if the power fails does the battery kick in. If they didn't do this, the battery would wear out quickly.