In addition to checking CPU usage, sort the listings in the “Real Mem” column to see if any are taking a large amount of RAM, and quit them. One culprit that may take up a large amount of RAM is Safari, but sometimes background system processes such as “mds” or “mdworker” may also take a large amount of RAM or CPU if they are not working properly. System Console In addition to Activity Monitor, the system will show process output (including errors and warnings) in the system console and system logs. These can be exceptionally useful resources for determining if applications and system processes are crashing or not working properly. To access the system logs and console output, go to the /Applications/Utilities/ folder and open the Console program. In here you can select the All Messages section to view live output from running processes, or look up recent crash logs in the System or User Diagnostic Reports sections. Even if you do not know what to look for, if you see a specific warning or message output to the console when the slowdowns occur then that information may be useful to a technician, and you can easily copy it into an e-mail if needed.