mrf_csspr Author

Level 1

0 points

Mac running slow and fan running at high speed

MacPro1,1, osx 10.7.5, 8gb ram

Posted on Jan 27, 2015 5:24 AM

Reply

4 replies

Level 10

265,054 points

Jan 27, 2015 5:26 AM in response to mrf_csspr

Runaway applications can shorten battery runtime, affect performance, and increase heat and fan activity - Apple Support

Reply

mrf_csspr Author

Level 1

0 points

Jan 27, 2015 6:07 AM in response to stedman1

Thanks for the advice, but unit runs all the time on high speed including on booting an external system and fails to boot on asd 3S108 diagnostic. Only on AST/MRI gives me that error. It could be a bad CPU or MLB?

Reply

Level 10

265,054 points

Jan 27, 2015 6:37 AM in response to mrf_csspr

Check the article below for instructions to reset the SMC and PRAM.

Intel-based Macs: Resetting the System Management Controller (SMC) - Apple Support

Reply

Level 10

210,519 points

Jan 27, 2015 6:52 AM in response to mrf_csspr

3S108 could mean a sensor problem

http://www.macissues.com/2014/03/21/how-to-run-and-interpret-apples-hardware-tes ts-on-your-mac/

Reply

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

Mac running slow and fan running at high speed

Welcome to Apple Support Community

A forum where Apple customers help each other with their products. Get started with your Apple Account.

Learn more Sign up