iMac 2011 RAM question

[gregof75]

Hi,

I would like to upgrade RAM in my 27" iMac (mid 2011) that has built 2x2GB RAM, can I add 1x4GB and 1x8GB RAm to get maximum 16GB?

Thanks for your advice!

 

[redheeler]

You can, but I generally recommend against not using a matched pair due to a slight decrease in speed.

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Maybe add 2x4 GB to make 12 GB?

 

[gregof75]

Thanks,

acctually I bought them already and I have a problem with 8GB RAM by Crucial. Any other configurations work fine, single 4GB works fine, 2x2GB + 4GB, but 8GB seems to be not recognised.
I have read that PRAM reset might help, can you confirm this or do you have any other advice how to make 8GB RAM working.

Cheers

 

[redheeler]

Thanks,

acctually I bought them already and I have a problem with 8GB RAM by Crucial. Any other configurations work fine, single 4GB works fine, 2x2GB + 4GB, but 8GB seems to be not recognised.
I have read that PRAM reset might help, can you confirm this or do you have any other advice how to make 8GB RAM working.

Cheers

Unlike the 21.5", a 2011 27" should take an 8 GB (it actually maxes at 32 GB, not 16 GB). A PRAM reset couldn't hurt.

 

[Pieterr]

I have a problem with 8GB RAM by Crucial.

What type of memory did you buy? Is it exactly this type? CT8G3S1339MCEU

 

[gregof75]

8GB DDR3 PC3 10600 1333Mhz

http://www.amazon.co.uk/gp/product/B006FWLS1C?ref_=pe_1909131_65443131_tnp_email_TE_AMZLdp_1

 

[Pieterr]

That is the M version, not the MCEU version.

http://www.amazon.com/Crucial-CT8G3S1339MCEU-Memory-8-GB/dp/B008PJXL1S

 

[gregof75]

That is the M version, not the MCEU version.

Well, so is the difference?
M version is still for Macs.
http://www.crucial.com/usa/en/memory/ct8g3s1339m

And for other buyers it work.

 

[Pieterr]

You could return the 4GB one and buy another 8GB one, so that you can use them as a pair.