How to solve Mac 10.10 Yosemite WindowServer High CPU usage in Activity Monitor

First step: disconnect any external or secondary monitors, if any is present. The video memory allocation leak can also happen if you have a system with an integrated card, like Intel, with no external monitors attached.

Second step: Shut down your machine and enter Safe Mode (press shift once you turn on your computer again, more info below). Once you’re there, fix your disk permissions.

Guide of how to access Safe Mode: OS X: What is Safe Boot, Safe Mode?

Third step: From Safe Mode turn off your machine again and reset your System Management Controller (SMC). There are different methods, depending on machine, to do this. To know what method applies to yours read the following guide.

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

Fourth step: Once your machine completes a full boot after resetting the SMC turn it off again and reset your PRAM (THIS IS THE MOST IMPORTANT STEP, BUT THE PREVIOUS ONES ARE ESSENTIAL FOR THIS ONE TO WORK). The PRAM stores small bits of data that indicate our Apple computer how to interact with the devices connected to it, including monitors and video cards. It also affects software.

To reset it you should hold the OPTION, COMMAND, P and R keys in your keyboard immediately after turning on your machine again.You’ll hear the start up chime, continue pressing the keys until the machine boots and the chime starts A SECOND TIME, then release. IF YOUR YOSEMITE INSTALLATION LOCKS UP AT A BLACK SCREEN AFTER THIS, DONT PANIC! It’s normal, just turn off your computer and let it boot again.

More info about PRAM: OS X Mavericks: Reset your computer’s PRAM

Voila, reconnect your external displays and enjoy your system.

Source: https://discussions.apple.com/thread/6623697

• About the Author
• Latest Posts
• Community Contributor

About Earnie Rhyker

tech pioneer | intellectual BadAss | ethical lifehacker | WordPress Developer & Polyglot | information activist | blogger | added value services provider | multimedia enthusiast | senior linux server administrator | geek | bitcoin investor | laptop entrepreneur | open source contributor | hackintosh fanatic | charity donator | accredited top MLM networker & internet marketer 2014-2016 @ BFH | digital expat

• My Dutch / NL WordPress Translation contributions: October 2022 - October 9, 2022
• My Dutch / NL WordPress Translation contributions: August 2022 - August 23, 2022
• [NL] Ultra Light digital nomad Europe travel with Ryanair / Wizz Air - August 20, 2022
• My Dutch / NL WordPress Translation contributions: July 2022 - July 27, 2022
• My Dutch / NL WordPress Translation contributions: April 2022 - April 2, 2022

View All Posts

Communities I have been 'hanging out' regularly over the past two decades. 

• Nomadlist.com since 2022-04
• Empire.Kred since 2021-07
• Karma-Lab.com since 2019-01
• Invision Community since 2018-05
• Insanely Mac since 2018-02
• eGPU.io since 2017-04
• Tech Inferno since 2016-08
• forum.VestaCP.com since 2016
• WordPress.org since 2015-12
• Couch Surfing since 2014

• BitcoinTalk.org since 2014-03
• Warrior Forum since 2013-07
• Empire Avenue since 2013
• forum.OSXLatitude.com since 2011-08
• Envato (i.e. CodeCanyon) since 2011-07
• TripAdvisor since 2010-09
• MoneyMakerGroup.com since 2007-03
• HardWare.info since 2003-08
• SynthForum.NL since 2001-11
• gathering.tweakers.net since 2000-11

Note: links go to my profile on those respective sites. Connect with me if you like.

• EarnWithEarnie.io since 2022
• EarnWithEarnie.net since 2018

• BestProfitsTeam.com since 2017
• CycleClubMembers.com since 2015
• BestSTIFORPteam.com 2013-2021