Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

HappyDude20

macrumors 68040
Original poster
Jul 13, 2008
3,688
1,479
Los Angeles, Ca
I've been reading many threads on the matter here already and I'm seeing many people successfully inserting their 1600mhz 8GBs of RAM into their 2009 unibody MBP that is suppose to only run 1066mhz RAM, but of course the computer is allowed for this to work..

However I'm holding here 8GBs of Kingston RAM, 1600mhz and would love for it to work on my MBP. However upon inserting these sticks I'm greeted with only a black screen and three odd beeps. Upon my putting in the original 1600mhz 4GBs of RAM that came stock with the MBP, the issue goes away. I've also done this one stock at a time and as you would expect, the stock works on a single basis but the Kingston does now.

I'm seriously stumped only because so many of the community seems to have varying results.
 
I've been reading many threads on the matter here already and I'm seeing many people successfully inserting their 1600mhz 8GBs of RAM into their 2009 unibody MBP that is suppose to only run 1066mhz RAM, but of course the computer is allowed for this to work..

However I'm holding here 8GBs of Kingston RAM, 1600mhz and would love for it to work on my MBP. However upon inserting these sticks I'm greeted with only a black screen and three odd beeps. Upon my putting in the original 1600mhz 4GBs of RAM that came stock with the MBP, the issue goes away. I've also done this one stock at a time and as you would expect, the stock works on a single basis but the Kingston does now.

I'm seriously stumped only because so many of the community seems to have varying results.

Mixing one of your 2GB modules plus a 4GB will almost certainly work.

A second option would be using Thaiphoon Burner, which can assign a new descriptor to a RAM module. In other words, your module would inform EFI that it is a 1066MHz module. But if I'm not wrong, this approach doesn't work with Kingstons because they have read only access to their descriptors. In my case, I made it successfully work with Corsair Value modules.
 
  • Like
Reactions: esbardu
I'm confused, are you trying to place 2 sticks of 4 GB or 2 sticks of 8 GB in your 2009 MBP?

According to spec, the limit is 8 GB total, it's possibly why the computer can't deal with 2 sticks of 8 GB each.

In the event you're going for 8 GB total, 1600 MHz RAM shouldn't matter as the computer will just adjust the speed to 1066 MHz (it's normal, that's all it can handle) - there's a possibility the RAM is bad/damaged.
 
I've been reading many threads on the matter here already and I'm seeing many people successfully inserting their 1600mhz 8GBs of RAM into their 2009 unibody MBP that is suppose to only run 1066mhz RAM, but of course the computer is allowed for this to work..

I was never able to get 1600MHz RAM to work in my mid 2009 13" MBP. The 1333MHz stuff did work fine though.
 
I was never able to get 1600MHz RAM to work in my mid 2009 13" MBP. The 1333MHz stuff did work fine though.

It may have something to do with voltages. As long as voltages match and there is at least on module with its SPD descriptor saying it's a compatible module, they should work.

Example:
1GB 1.5V DDR3 1066MHz + 4GB 1.5V DDR3 1600MHz should work on a 2009 MBP, delivering 5GBs total.

However, if you want installing:
2x4GB 1.5V DDR3 1600MHz module, it wouldn't work since there isn't at least one 1066MHz module.

The only way to solve the issue is by using a SPD editor like Thaiphoon Burner. Some modules (like most Kingston ones) are read-only, but Corsair Value ones allow changing their SPDs so they're recognized as 1066 modules.

1600MHz modules for newer Macs are usually 1.35V, which can be the cause of the incompatibility.
 
  • Like
Reactions: esbardu
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.