I recently upgraded the memory of a mid-2012 Macbook Pro 13". Now I have 2x 2GB DDR3 SO-DIMMs running at 1600 MHz PC3-12800 @ 1.35V left over from the process. I noticed that the memory in the mid-2009 iMac 21.5" is user-upgradable and can accommodate up to 4 DDR3 SO-DIMMs running at 1066 MHz PC3-8500 DDR3 (presumably @ 1.5V?). The iMac has only 4GB of memory, so I assume it uses only 2 of the 4 slots with 2GB memory each. Can I put the memory of the Macbook Pro into the iMac without causing harm?
The memory DIMMs are all DDR3, and I know the higher frequency memory will run at only 1066 MHz. But is the memory from the Macbook able to operate at what I presume would be 1.5V used by the iMac?
Also, I've heard some stories about degraded performance when mixing memory of different types because the Mac not only tries to match the frequencies but also the memory timings (CAS, RAS, etcetera). How can I check if this is an issue on Mac OS X Snow Leopard?
The memory DIMMs are all DDR3, and I know the higher frequency memory will run at only 1066 MHz. But is the memory from the Macbook able to operate at what I presume would be 1.5V used by the iMac?
Also, I've heard some stories about degraded performance when mixing memory of different types because the Mac not only tries to match the frequencies but also the memory timings (CAS, RAS, etcetera). How can I check if this is an issue on Mac OS X Snow Leopard?