If your Mac laptop is running very loudly (the fan) and everything seems sluggish, you might have an application running in the background that's causing the machine to slow down, and to run at higher CPU speeds than normal (which makes the fan run faster and more loudly).
You might be able to find the application causing the high CPU utilization by doing this:
- Hold down the option key on the keyboard
- Click the battery symbol in the menu at the top of the screen
- Wait for 5-10 seconds for it to gather power information (will show up in the middle of the menu)
- Look at the list of applications using significant power. See if you can quit any of the apps listed that are using a lot of power. If you can't make it quit, try Force Quitting (on the Apple menu) that application, and see if this helps. If the only app listed is your web browser, look at the tabs you have open, and see if a webpage is stuck in one of the other tabs.
