Max Ram for a Macbook Pro

[arstacey]

I have a mid-2009 13" Macbook Pro MB990LL/A. This unit uses DDR3 1066Mhz memory and is listed as supporting up to 8GB of ram. Of course at the time you could not get a single 8GB stick of ram. Does anyone know if these can support 16GB (2 x 8GB) of DDR3 1333Mhz RAM?

On a pc or server motherboard often the max ram listed is just the number of slots times the largest available dimm at the time, and faster ram will scale back to the speed of the motherboard. When larger dimms come out you can almost always go higher than the listed specs. If you cannot do this with Apple products, could someone explain what is prohibiting the machine from accepting the larger dimms?

 

[GGJstudios]

I have a mid-2009 13" Macbook Pro MB990LL/A. This unit uses DDR3 1066Mhz memory and is listed as supporting up to 8GB of ram. Of course at the time you could not get a single 8GB stick of ram. Does anyone know if these can support 16GB (2 x 8GB) of DDR3 1333Mhz RAM?

No, 8GB is the max.

You can find specs on all Apple products, including maximum RAM:

• By visiting EveryMac.com: Actual Maximum RAM
• By selecting your model on the Crucial Memory Advisor™ Tool to find RAM information
• By using Mactracker
• By entering your serial number here to find specs for your model.
  (Be aware that some models can use more RAM than Apple shows. Check EveryMac to verify actual usable RAM.)

 

[arstacey]

Do you know what prevents it from accepting 16GB of ram? Is it a bios setting or something in OSX? I know it is listed as 8GB Max, but again that was the max that was available at that time in a 2 dimm configuration.

 

[GGJstudios]

Do you know what prevents it from accepting 16GB of ram? Is it a bios setting or something in OSX? I know it is listed as 8GB Max, but again that was the max that was available at that time in a 2 dimm configuration.

It's not a limitation of the available RAM modules. It's a hardware limitation.

 

[Feed Me]

It's not a limitation of the available RAM modules. It's a hardware limitation.

What is the nature of this hardware limitation?

 

[GGJstudios]

What is the nature of this hardware limitation?

It's a limitation in the chipset.

 

[arstacey]

Gotcha. Thanks for the input.

 

[andyriot]

Interesting idea though... has anyone tried it?

 

[T5BRICK]

Interesting idea though... has anyone tried it?

I'm sure someone has. I Imagine it either didn't work at all or showed up as a partial capacity.

 

[felic]

Okay continuing on from where this thread left off as I have a related question on RAM compatibility to MacBook Pro 13" mid-2009 model. Officially Apple states max RAM speed as 1066mhz. Would a higher speed at 1600mhz be compatible?

 

[ammusk]

Okay continuing on from where this thread left off as I have a related question on RAM compatibility to MacBook Pro 13" mid-2009 model. Officially Apple states max RAM speed as 1066mhz. Would a higher speed at 1600mhz be compatible?

Yes but it would run at the slower 1066mhz

 

[felic]

Yes but it would run at the slower 1066mhz

Oh I see. So the 2009 MBP was built to run at that speed as a maximum I guess?

Thanks for the response.