Here’s how to test 16GB of RAM on the new MacBook Pro.
There will be myriad reviews of the new Macbook Pro with Retina Display. Barring any major malfunctions, they will generally be glowing. That’s because it is the best PC ever built — but it’s not without its own unique risks.
For years, computer displays have not made much progress. The Retina display on the new Macbook Pro changes that. As a perennial fan of display technology, it’s been a long time since I’ve been excited about a new computer, and I bought this one sight-unseen minutes after release. Then I saw the detailed picture of the motherboard, and after initial awe of the beautiful design, felt the tingle of an unfortunate paradigm shift. “Is that… wait… soldered-on RAM? with no upgrade slots?”
I quickly cancelled my order for an 8 GB model and upgraded to 16 GB.
That’s a lot of non-user-replaceable RAM, a lot of bits to store, and a lot of potential for failure. Memory is now so small and sensitive that even cosmic rays can cause it to malfunction. Cosmic freakin’ rays. My first Intel architecture computer had soldered-on RAM, and it had a single hardware failure: bad RAM. So, the first thing I did when I got this new laptop was find the Mac-equivalent of the tried-and-true memory verifier, memtestx86.
Apple, like Dell, must run its units through several tests before they’re shipped. Dell’s factory ran initial “quick tests” on each computer, and did a fairly rigorous job in the time allotted, but it’s a long trip from Shanghai, so here’s what to do to make sure all 16 gigabytes of memory are functioning perfectly.
Download the handy memtest package provided by this good fellow, reboot while holding down Command-S to get to the prompt, and then run:
memtest all 2
The two iterations run for a couple of hours total, and the results should look like this:
Now that the vast expanses of new bits have been vetted, I know that at least at this point in time, the new Mac is completely operational, and all of its circuits are functioning perfectly. The awesome Pelican 1490 should help keep it that way.
Update two days later: Received a call asking what “Parity NMI System Halted” on a Windows box means. It means computer memory fails, and it’s a good thing to verify your RAM.