RAM overload

[szolr]

What exactly happens if I put 16 GB of RAM in an early 2011 Macbook Pro? Will it just not turn on? Will it melt? Will it only recognise 8GB? No-one's ever actually told me so I don't know.

Also what if I put an 8 GB chip in one slot and leave the other empty-how will that compare to a Macbook Pro with 2 4GB chips?

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Apparently Crucial's scanner says my system can support 16 GB of RAM. But Apple's site disagrees (it says 8 GB). Now I'm really confused...

 

[RedReplicant]

Your machine will run 2x8GB(16GB) perfectly fine.

Running a single 8GB stick would lose you some memory bandwidth since it's running single channel vs dual channel. Best to stick to pairs. You could leave one of the stock 2GB sticks and stick the 8GB stick in next to it if you wanted.

 

[FrancoisC]

I'm guessing it will be just fine, I installed 16GB in my 2011 mini, price went down a lot and I'm running a lot of VMs.

 

[theSeb]

Nothing to be confused about. Your computer supports 16 GB (2x8). The apple specs were written when 8 GB sticks were not readily available. They do not normally update these specs.

 

[szolr]

Nothing to be confused about. Your computer supports 16 GB (2x8). The apple specs were written when 8 GB sticks were not readily available. They do not normally update these specs.

Oh... Cool. Guess that'd explain why the iMac pages say they support 16 GB of RAM-they were released later.

 

[RedReplicant]

The iMacs have 4 slots, they support 32GB.

 

[szolr]

You could leave one of the stock 2GB sticks and stick the 8GB stick in next to it if you wanted.

That sounds a good idea. Would it lose me any performance or anything like having only one channel occupied would?

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The iMacs have 4 slots, they support 32GB.

Ah, right. Seems I've learnt a lot in this 1 thread. Thank you everyone.

 

[RedReplicant]

Hm, well I am not sure with the setup that Apple has on these boards but Intel has a 'flex channel' mode that would run the first 2GB of each stick in dual channel but leave the extra 6GB of the 8GB stick to single channel.

The performance loss isn't anything you'd really notice in the real world unless you're doing heavy encoding on a daily basis or something and even then it would probably be more than made up by the reduction in swapping since you've got enough memory to keep everything held in RAM.

 

[szolr]

Hm, well I am not sure with the setup that Apple has on these boards but Intel has a 'flex channel' mode that would run the first 2GB of each stick in dual channel but leave the extra 6GB of the 8GB stick to single channel.

The performance loss isn't anything you'd really notice in the real world unless you're doing heavy encoding on a daily basis or something and even then it would probably be more than made up by the reduction in swapping since you've got enough memory to keep everything held in RAM.

Sure. 10 GB RAM is definitely better than 4 GB.