My Macbook Pro came with 4GB of RAM in 2 2GB modules. In December, I ordered 8 GB (2 4GB modules) of RAM from Crucial so I could max out the RAM in the machine, as I intend to keep it for a while. Early in January I started to see applications crash. VMWare Fusion became almost unusable.

I had never seen this behavior from my Mac before, so figured the new RAM had something to do with it, but wanted to verify my assumption before blindly blaming Crucial for bad RAM. At that point I had to learn how to best test RAM on a Mac. On a PC, I would have booted a CD running memtest86, but none of my Internet research indicated that was possible for the Mac. Instead, I had to install and boot the machine into single user mode in order to run memtest with the least amount of interference from running programs. I wanted to document what I had done in a blog post so I could remember next time. Note: This article involves configuring your Mac in a way that could make it difficult for you to boot it normally if you don’t know what you’re doing. If you don’t feel comfortable following these instructions, take your Mac to a technician who not only feels comfortable fixing your computer, but is also competent to do so.

Question: Q: Memtest86 - Memory Diagnostic Tool. Memtest86 is a memory test for x86 (PC) computers. There have been problems with the OS X version of Memtest. On ECC memory in Intel Mac Pro. On Intel Macs, you can boot a Vista DVD and it includes. And which means it is running without an OS, more like single user. How write batch executable file for mac. The version of Windows, Linux, or Mac being used is irrelevant for execution. However, you must use either Windows, Linux or Mac to create a bootable CD,.

To tell the Mac to boot into verbose 64-bit single user mode, go to Applications/Utilities/Terminal, and type. Memtest version 4.22 (64-bit) Copyright (C) 2004 Charles Cazabon Copyright (C) 2004-2008 Tony Scaminaci (Macintosh port) Licensed under the GNU General Public License version 2 only Mac OS X 10.6.6 (10J567) running in single user mode Memory Page Size: 4096 System has 2 Intel core(s) with SSE Requested memory: 7555MB ( bytes) Available memory: 7555MB ( bytes) NOTE: Memory request is too large, reducing to acceptable value.

Allocated memory: 7343MB ( bytes) at local address 0x1000000 Attempting memory lock. Locked successfully Partitioning memory into 2 comparison buffers. Buffer A: 3671MB ( bytes) starts at local address 0x000000 Buffer B: 3671 MB ( bytes) starts at local address 0x00000001e67fd760 Running 1 test sequence. (CTRL-C to quit) Test sequence 1 of 1: Running tests on full 7343MB region. Stuck Address: ok Linear PRN: ok Running comparison tests using 3671MB buffer. Random Value: ok Compare XOR: ok Compare SUB: ok Compare MUL: ok Compare DIV: ok Compare OR: ok Compare AND: ok Sequential Increment:ok Solid Bits:ok Block Sequential:ok Checkerboard:ok Bit Spread:ok Bit Flip:ok Walking Ones:ok Walking Zeroes:ok All tests passed! Activating office for mac.