My Mac (Mid 2009- MacBookPro5,5) laptop installing OS 10.8.2.
Currently, it is using 2 x 1GB (1066 Mhz).
My friend gave me 2 x 2GB (1600 Mhz) of his 2012 Mac.
After installing 2 x 2GB (1600 Mhz) on my Mac, it can
not boot but can not start OS. This is the error that show on boot start up screen:
But it is possible to install 1x 1GB (1066) + 1x 2GB (1600). The system can down-clock it to both 1066 Mhz. But what i still have 1 x 1GB (1066) + 1x 2GB (1600) left!
My question is: Any better solution than using 1x 1GB (1066) + 1x 2GB (1600)?
More certainly, is there any way to install 2 x 1600 Mhz? (even down-clocking to 1066 is accepted). (currently, 2x1600 Mhz can not startup OS).
Edit 1: 4 RAM are healthy.