Mac running like a snail after 15 minutes After booting up my Mac (2011) it runs fine for the first 15 minutes then runs like a snail. My memory and CPU usage is fine and I have scanned for viruses countless of times an comes back with nothing. I have checked my spotlight search and apps running in the background (all the tips everyone gives you to check). If anyone has any suggestions it would be much appreciated.
Here are some ideas for troubleshooting a slow Mac


Open the console app (it is located in the utilities directory). Watch the log for any strange behavior.
Hold the shift key while booting to boot into safe mode, see if the issue continues. 
Turn off half of the programs in the startup, see if issue persists, then turn off the other half. Keep repeating until you find the program that is the culprit. 
Try creating a new user account
Lastly, backup to time machine, and format.