An urban legend says that if a user replaces a 2GB RAM module with a 4GB RAM module in a Mid-2007 15-inch MacBook Pro, that it will result in a total of 6GB of RAM (if the other RAM slot already has a 2GB RAM module).
Is this true ???
MacBook Pro, Mac OS X (10.7.4), 4GB RAM; hp D110a (AIO Prntr); iPod Nano (5th gen.)
Yes, you can install up to 6GB, 4GB + 2GB. Unless you need or can use 6GB, the system will operate a little bit faster with matched memory, is, 2x2GB. It's not huge ... 3% to 5% in application testing. You can see OWC memory options here.
Does it matter WHICH slot the 4GB module is plugged-into ???
I'm not aware of anything that says a specific slot has to be used. I would put it in the top slot, only removing one existing memory card, button it up, turn it on, and click the apple on the menu bar, and about this mac, to see what the system recognizes.
6GB RAM possible in Mid-2007 15-inch MacBook Pro ???
