Macbook Pro (2011, 2.2ghz) - Slow after Battery problem?

Question

Level 1

0 points

Macbook Pro (2011, 2.2ghz) - Slow after Battery problem?

Hi,

on saturday my mac crashed and didn't boot anymore. The green lamp from the charger wasn't glowing anymore either. So i went to the appstore to get a check on it. They reset the battery (unplugged it?) and it booted again. But it feels like my macbook is slower now..

Using programs feels slower. The first time i realized it was slower is when i played Minecraft afterwards. Usually i get 500 fps but now its only 20. I didn't update anything in the meanwhile. This was on windows though. So i tried it on Mac OS X but same performance.

I work in Flash Builder on Mac OS X and it also feels much slower now.

I think it somehow affected the CPU. I have this project i am working on that uses Multithreading and it also feels much slower (the system freezes while calculating stuff on a second thread, and continues when its done). Could also explain the performance in minecraft.

Yesterday i upgraded my Ram to 8GB so i had to reinstall windows on my second partition. After the installation and installing all updates and drivers, i did this weird system check that gives you a number how good it performance.

Before the re-install, the Ram had the lowest value with 5.2. I believe my CPU was at 6.

But now i get 4.6 for the CPU and it`s the lowest value.

Could it be that they reset something on the cpu when resetting stuff at the appstore?

I had no time yet to go back to the appstore, my work schedule is very busy for the next 2 weeks and i need the mac to work on.

Wonder if anyway has an idea of what it could be.

Thanks,

Sven

MacBook Pro, Mac OS X (10.6.8)

Posted on Aug 23, 2011 10:47 AM

Reply

Answer 1

Kiyaku Author

Level 1

0 points

Aug 29, 2011 5:55 PM in response to Kiyaku

I did more tests today.

I used a benchmark (called geekbench) to see what results i would get compared to the avarage online + my coworker, who has the same macbook (exact same model, memory, cpu, etc..).

The average was ˜9.900 online, my coworker got ˜10.000 and i get 2.800 (when all applications are closed).

Me: http://i.imgur.com/S9zoZ.jpg

Coworker: http://i.imgur.com/IoMis.jpg

I also checked it under windows (fresh install, all updates installed), pretty much same result (2.500).

So there is definitely something wrong. I went to the apple store again few days ago but they said it's all good and it must be an issue with windows and they can't help me, which i find a bit.. strange.

But now that i have actual data from Mac OS, i can go back there soon (still have to wait till wednesday cause i need it for work).

I'm wondering if it is an voltage problem, so i installed iStats to see what it shows, but i don't know much about those things so i wonder if anyone can see something suspicious:

http://i.imgur.com/MCEmv.png

Thanks!

Reply

Answer 2

Kiyaku Author

Level 1

0 points

Aug 30, 2011 12:23 AM in response to Kiyaku

And another update.

After someone told me that the CPU Speed listed on the System profiler is not really the current CPU Speed, but more like what's on the chip, i booted windows to check the real CPU speed with CPU-Z (couldn't find any tool for mac that can do it) and this is the result:

http://i.imgur.com/yrjHd.jpg

So it looks like, for some reason, my CPU is way too slow. I've heard that old macbooks reset the clock speed to 1ghz if you replaced the battery, i guess something simliar is the case here?

I assume it's not easy to "fix" that on my own, could't find much information about how to actually change your clock speed other than with one tool that does not support i7, and it would also void your warranty i guess.

But with that test i can hopefully convince the people at the apple store that there is something wrong and get them to fix it.

Reply

Answer 3

Aug 30, 2011 2:33 AM in response to Kiyaku

There might be some thread/process which has max'ed out on CPU usage. Can you fire up activity monitor, select all processes and see if theres anything suspiscious? If there's any user initiated thread thats causing the surge in the CPU usage then you've found your culprit.You may want to try killing the thread and then see if it helps.

Reply

Answer 4

wjosten

Level 10

95,369 points

Aug 30, 2011 2:54 AM in response to Kiyaku

If you run a MacBook Pro, without a battery installed, the system will automatically throttle back the CPU to insure that the CPU's power requirements do not exceed that of the power brick's ability to provide. I'm wondering here if your problem is somehow related to this.

Reply

Answer 5

Kiyaku Author

Level 1

0 points

Aug 30, 2011 2:00 PM in response to wjosten

Okay i just solved the issue.

Simliar to your answer, i read something that the macbook throttles down the CPU to around 1ghz if there is a battery problem.

I guess that's what happened here too.

So the System Profiler does not show the correct CPU speed. Instead i found this little helpful line for terminal:

sysctl hw.cpufrequency

which shows the correct CPU speed, and it was indeed 730mhz.

So i reset the SMC by shutting down the mac, pressing left-shift + control + options + the power button for a second, and then turn the mac on again.

It resets the CPU speed back to my 2.2ghz and everything is fixed now 🙂

The Geekbench score was 7700 in the end, still not as much as my coworker but he has lion installed. So i just bought lion, upgraded, installed all updates and tada, i get 10.000 as well.

A bit disappointed that the apple store couldn't figure out that my CPU was underclocked :/

Anyway, hope this thread helps other people as well and thanks for your input!

Reply

Answer 6

wjosten

Level 10

95,369 points

Aug 30, 2011 2:03 PM in response to Kiyaku

You're welcome.

Reply

Answer 7

bian6

Level 1

0 points

Jan 3, 2013 4:38 PM in response to Kiyaku

I did that with my mbp early 2011 that have the same problem, but know its run fine but the battery metter gone and the machine runs all the time with the fans on. Anyone have the same problem?

Thanks

Bian6

Reply

Answer 8

RoXy1988

Level 1

7 points

Jan 5, 2013 12:59 PM in response to bian6

I have the same issue ! I noticed it few days ago .. didn't find a solution though

Reply

Answer 9

potcha

Level 1

0 points

Apr 9, 2014 2:03 PM in response to Kiyaku

I made an account here just so I could thank you. I had been struggling with this issue for a while, trying desperately to figure out why the macbook was so sluggish after I had replaced the battery. I did tons of troubleshooting before I realized how underclocked the CPU was and your answer fixed it instantly. You have made my entire week with this little bit of information. I hope others with this problem are fortunate enough to land on your post.

Reply

Answer 10

Nov 1, 2016 2:30 AM in response to Kiyaku

My battery status says "Replace now" and while sysctl hw.cpufrequency shows 2.7GHz, the Intel Power Gadget shows 800MHz. It has indeed become unusable.

An SMC reset doesn't seem to solve it.

MacBook Pro 13" (Early 2011)

CPU: i7 2.7GHz

Reply