Using Apple Hardware Test on computers with OS X v10.7 and earlier
AHT is located on the Applications Install Disc 2 and should be included with your computer or the MacBook Air Software Reinstall Drive on a MacBook Air (Late 2010). To start AHT on these computers make sure the Applications Install Disc 2 is inserted into the built-in optical drive, external Apple Superdrive, or for the MacBook Air (Late 2010) be sure the MacBook Air Software Reinstall Drive is inserted into a USB port. Then, follow steps 1-6 outlined in the previous section of this article.