Issue with heat and battery life

[Tim018]

I have owned two different late 2008 macbook pros, both with the same problem.

I know most macbooks do not reach their advertised battery life, but this one seems a bit ridiculous.

For some reason, this machine will run great, around 48-52c and get around 3 hours of battery life. Then all of a sudden, doing the same activities (even just writing a paper with nothing else open) it will heat up to 65-75c and get around 1.5 hours. A simple smc reset will put it back in its place and it will run fine for a day or two. Then it will heat up again and drain the battery, repeat process.

Any particular reason it would do this? I'm running 10.7.3 right now, but it has done this with 10.6 also. Is this just a fluke with the 2008's and i should sell it and get a newer one?

Thanks for any advice

Tim

 

[lgwells1]

Open up Activity Monitor, the next time your fans are kicking into warp drive, check the processes and see what is causing it. Make sure you have "View All Processes" selected.

 

[Tim018]

Open up Activity Monitor, the next time your fans are kicking into warp drive, check the processes and see what is causing it. Make sure you have "View All Processes" selected.

Yep, tried that. I have "all processes" selected and usually its 95-98% idle while in this condition...

I use smc fan control to keep the fans at 3k-4k also.

Sorry i forgot to mention these things.

 

[GGJstudios]

For some reason, this machine will run great, around 48-52c and get around 3 hours of battery life. Then all of a sudden, doing the same activities (even just writing a paper with nothing else open) it will heat up to 65-75c and get around 1.5 hours. A simple smc reset will put it back in its place and it will run fine for a day or two. Then it will heat up again and drain the battery, repeat process.

Any particular reason it would do this?

The heat is not affecting your battery life. Rather, some app or process is consuming system resources, which both drains the battery and generates heat. Launch Activity Monitor and change "My Processes" at the top to "All Processes", then click on the CPU column heading once or twice, so the arrow points downward (highest values on top). Then look to see what may be consuming system resources.

There are many factors that impact your battery life. See the BATTERY LIFE FROM A CHARGE section of the following link for details, including tips on how to maximize your battery life.

This should answer most, if not all, of your battery questions:

Apple Notebook Battery FAQ​

 

[Tim018]

The heat is not affecting your battery life. Rather, some app or process is consuming system resources, which both drains the battery and generates heat. Launch Activity Monitor and change "My Processes" at the top to "All Processes", then click on the CPU column heading once or twice, so the arrow points downward (highest values on top). Then look to see what may be consuming system resources.

There are many factors that impact your battery life. See the BATTERY LIFE FROM A CHARGE section of the following link for details, including tips on how to maximize your battery life.

This should answer most, if not all, of your battery questions:

Apple Notebook Battery FAQ​

True, I posted a little info above of what I usually do to keep temp down and check cpu usage. For example: an hour ago, the temperature was about 68c while i was writing my paper. then i did a smc reset and it is running at 47c now. nothing has changed in what i am doing, the reported cpu usage, or the surroundings. id be fine with that, except i had to do the same exact thing yesterday. how can i prevent this from happening again?

 

[GGJstudios]

True, I posted a little info above of what I usually do to keep temp down and check cpu usage. For example: an hour ago, the temperature was about 68c while i was writing my paper. then i did a smc reset and it is running at 47c now. nothing has changed in what i am doing, the reported cpu usage, or the surroundings. id be fine with that, except i had to do the same exact thing yesterday. how can i prevent this from happening again?

I suspect that the SMC reset isn't affecting your issue as much as simply restarting your computer in the process. The next time it happens, don't reset the SMC, but do restart your computer. See what happens. Also if a drive is constantly active or your CPU utilization is high (possibly with increased temps and fan speed) when you're not running any major apps, you can check to see if Spotlight is indexing by looking at the Menu Bar icon:

(not indexing)

(indexing) (pulsing dot)​

When it's indexing, you may also see increased CPU and RAM usage by the mds and mdworker processes in Activity Monitor.

 

[lgwells1]

When was the last time you opened up your machine and cleaned out all of the dust? I doubt this will cure your problem, but it is always a nice thing to do.

Can you see what processes are causing spikes in CPU usage? Usually your culprit right there.

 

[Tim018]

yeah, usually I see no abnormal CPU usage during the hot/short battery situation and generally a simple restart doesn't seem to have any effect. any other ideas? has anyone else had this problem? thanks to everyone who has posted ideas

 

[GGJstudios]

yeah, usually I see no abnormal CPU usage during the hot/short battery situation and generally a simple restart doesn't seem to have any effect. any other ideas? has anyone else had this problem? thanks to everyone who has posted ideas

The next time you're experiencing this, launch Activity Monitor and change "My Processes" at the top to "All Processes", then click on the CPU column heading once or twice, so the arrow points downward (highest values on top). Also, click on the System Memory tab at the bottom. Then take a screen shot, scroll down to see the rest of the list, take another screen shot and post them.