How to reset your PRAM and NVRAM on an Apple Computer
To reset the PRAM/NVRAM, please follow this
article on Apple's support site.
How to reset your System Management Controller (SMC) on an Apple Computer
To reset the SMC, please follow this article on Apple's support site at:
Only reset the SMC if you are having issues beyond the OS (ie, hardware issues, or if an Apple Tech directs you to.)
How to run Diagnostics
Follow the directions below on how to run Apple diagnostics in an event to check apple hardware for failures etc. These test may take up to 2 hours to complete depending on the type of hardware you have. Apple diagnostics checks all main components such as the CPU, on-board video, memory, and on-board bus/controllers. Apple diagnostics may not check (or the ability to check) external attached cards or devices.
On Intel-based Macs, on power up, hold the 'D' key until you get the Apple Diagnostics prompt.
On PPC-based Macs, on power up, press and hold the 'alt + option' combination until you get the Apple Diagnostics prompt.
Check if your Apple Computer is under Warranty
First, locate the serial number of your Apple Product. How To
Then, To check to see if your Apple Computer is under warranty, login below, or on Apple's Website.
From the page below, you can check to see if your machine is under warranty or not. This is useful to verify if your machine has AppleCare or any trouble tickets that are open.