That’s why Apple’s Hardware Test is a great option: it loads only a rudimentary operating system, which loads just the tests, ensuring that RAM isn’t occupied with anything else. This means, if you use Rember or memtest, to do it in Safe Mode (for anything requiring a graphic interface), or better yet, in Single User mode, as these will ensure as much RAM is available for testing as possible. Run in Safe Mode or Single User Mode: Since memory test programs can only test the RAM that is available, be sure to run it in as minimal of an operating system as possible. Therefore, I recommend you use more than one.Īpple’s new hardware test suite will run automatically and show you any results here.įor best results, you should run these RAM-testers under some special conditions: Each will test memory differently and some may miss a problem that another can detect. But, as I say, there are many of them just check the Mac App Store and search for RAM. You can also get a graphical wrapper for memtest, called Memtest, which is run from the Terminal command-line. In addition to Apple’s testing suite, there are plenty of third-party memory-testing utilities.

If everything is OK, you’ll see a message that states all tests passed and no problems were found. If the hardware test finds any faulty memory, it will list the faulty memory addresses.

Note that, if you have formatted your hard drive and reinstalled OS X, then the built-in hardware tests may have been wiped however, you can still load them from the Internet by holding the Option-D key combination (as opposed to just D) at startup when you hear the boot chimes.

On newer Macs, the tests run automatically when the utility is invoked it appears with a gray background instead of blue.

2013 macbook pro 3 beeps