ram: 1333 vs 1066 for 2009 mbp?

[TuiSong]

I've done a few general searches trying to figure this out, but most of the questions all seem to be involving putting the 1066 ram into a 1333 slot. I have a mac book pro, it current;y has only 2gb of ram (2x 1gb 1066mhz) and i have a new mac mini which is currently running 4gb (2x 2gb 1333mhz) I've just bought 8gb of ram for the mini because it grinds on a couple of applications we need to run. I'll have the 4gb spare, and wondered if there would be any issues with installing it into the mbp. It's a mid 2009 model

 

[Mersailios]

I would advise that you stick with 1066MHz DDR3 RAM for your MacBook Pro to avoid any potential compatibility problems.

Some owners have stated that while 1333MHz memory was detected as such in their MacBook Pros, they would encounter freezes and other anomalies; others have mentioned that their computers would flat out fail to turn on with the faster memory installed.

 

[alust2013]

The majority of the time it will work just fine. No harm in trying it out.

 

[Mr.Outside]

From personal experience I would say to stick with the 1066 MHz. I ordered 1333 MHz, installed, and my Mac wouldn't get beyond the boot screen.