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. If that works, just leave the bad RAM slot empty, and go with 'what works'.On newer Macs, the tests run automatically when the utility is invoked it appears with a gray background instead of blue.

Buy an 8gb DIMM and put it in 'the BOTTOM slot' (with the back off) If taking out the upper RAM makes the computer 'run as it should', then what I would do is: Try to boot and run that way a day or two. Remove the RAM DIMM 'nearest to you' (topmost slot with back off).

If you're STILL getting the display problems Put the back on and see if that changes anything. Clean off the contacts, then reseat the RAM back into the DIMM slots. take off the back cover (you need a Phillips #00 driver for the screws, and pay attention to where 'the long screws' go). Might be worth taking it in an having it replaced. Although this doesn't sound like a problem that would give you 'the three beeps'.ĭo you have a brick n mortar Apple Store anywhere close?Īpple -used to have- a free replacement program for the ribbon cable in the 2012 MBP's. The cable 'wears' the internal connections go bad, or sometimes it even 'shorts out' against the back cover. Also, the SATA ribbon cable that connects the internal hard drive to the motherboard (it's a 'known weak' component on the 2012-design non-retina MBP's).

RAM slot - intermittent contact from back of case 'pressing on' the topmost RAM DIMM (that's why you see it act up when you set it on a surface) If you get '3 beeps in a row' - that's an indication of 'RAM troubles'.

2012 macbook pro 3 beeps not ram or hd