MBA won't go faster than 800MHz

[ayeying]

So my Rev. A has been completely trouble free for a while now except today I noticed how my temps never reach above 70 deg C and the fans never leave 1800 RPM. I did some check and noticed my CPU speed is locked in at 800MHz no matter what load % it is.

I do not have CoolBook installed on this system since I never needed it. I tried resetting the SMC but it didn't work.

Anyone else might have something I can try?

 

[gr8tfly]

So my Rev. A has been completely trouble free for a while now except today I noticed how my temps never reach above 70 deg C and the fans never leave 1800 RPM. I did some check and noticed my CPU speed is locked in at 800MHz no matter what load % it is.

I do not have CoolBook installed on this system since I never needed it. I tried resetting the SMC but it didn't work.

Anyone else might have something I can try?

Do you have the latest firmware installed? http://support.apple.com/kb/HT1237 has the correct version and link to updater listed.

 

[ayeying]

I have all the firmwares installed when I received the system. I double checked and checked in Software Update. All software are up to date.

 

[gr8tfly]

I have all the firmwares installed when I received the system. I doubled checked and checked in Software Update. All software are up to date.

It might not show up in Software Update - it's worth a double-check in System Profiler.

There used to be a KB article on reduced performance when hot (even a note in the service manual), but it's been removed. I know the Firmware update addressed performance and stability and there was a SMC update which addressed fan control.

I agree that 70c isn't all that hot, though.

I also found this update: MacBook Air Update What’s New in this Version
This update is recommended for all MacBook Air computers, and addresses issues with video playback and processor core idling.

Again, I'm not sure that one showed up in Software Update. You can check in your /Library/Receipts and see if it's there (or just download it - it won't install if it's not needed - it also might be included in later 10.5 updates)

edit: I just tried the "MacBook Air Update" on our Rev. A - It simply said it was "not needed on this machine". I probably already had installed it, but figured I'd double check. Anyway, as I said, it won't hurt to make sure.

 

[ayeying]

I double checked and all my firmwares were installed from factory because I bought this system refurbished not too long ago.

Anyways, I re-did a SMC reset and this time it worked. My system now returns back to 1.6GHz when the load requires it. I'm not sure why my first time didn't work, maybe I didn't do it properly.

 

[gr8tfly]

I double checked and all my firmwares were installed from factory because I bought this system refurbished not too long ago.

Anyways, I re-did a SMC reset and this time it worked. My system now returns back to 1.6GHz when the load requires it. I'm not sure why my first time didn't work, maybe I didn't do it properly.

That's good news. I know sometimes it's easy to miss a key using the "Vulcan-neck-pinch" combinations.