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RAM Upgrade ? new iMac i5

The new iMac is out today- 2.7GHz Quad-Core Intel Core i5

They come with "4GB 1333MHz DDR3 SDRAM - 2x2GB"

What I would like to know if I bought an extra 2 - 4GB RAM,

can I put them side by side(4 slots) in the iMac for a total 12GB of RAM.

Would mismatched ram throw it out of balance, and slow the iMac or will it speed it up?


Thank you

2.7GHz Quad-Core Intel Core i5-OTHER, Mac OS X (10.6.7)

Posted on May 3, 2011 8:15 AM

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Posted on May 3, 2011 11:25 AM

What you are proposing (adding 2x4GB RAM modules) will speed up your machine because you’ll swap code in and out of memory more often depending upon the demands you place on the machine. Activity Monitor (Utilities) will show you how much memory you are using and indicate if more memory will help overall performance. If you are seeing that most of your memory is used frequently, consider upgrading. 12 GB is typically a very healthy amount of RAM that will keep your programs happy. 8 GB is likely sufficient for most people’s uses. Some programs will use all the memory you through at them such as graphics and video intensive programs but may not justify going beyond 12 GB.


If you install memory modules in matched pairs you will receive the maximum memory throughput (dual channel memory access paths for the iMac). If you added a single 1x8GB memory module, you will see degraded memory access because the system will only use a single channel access path.


Someone will be recommending you do not buy the extra memory from Apple but today’s prices are cheap compared to what I paid in 2009 so it still seems a reasonable option if you prefer Apple memory. If you go with another provider, just make sure they are reputable and guarantee the memory.

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May 3, 2011 11:25 AM in response to woodie

What you are proposing (adding 2x4GB RAM modules) will speed up your machine because you’ll swap code in and out of memory more often depending upon the demands you place on the machine. Activity Monitor (Utilities) will show you how much memory you are using and indicate if more memory will help overall performance. If you are seeing that most of your memory is used frequently, consider upgrading. 12 GB is typically a very healthy amount of RAM that will keep your programs happy. 8 GB is likely sufficient for most people’s uses. Some programs will use all the memory you through at them such as graphics and video intensive programs but may not justify going beyond 12 GB.


If you install memory modules in matched pairs you will receive the maximum memory throughput (dual channel memory access paths for the iMac). If you added a single 1x8GB memory module, you will see degraded memory access because the system will only use a single channel access path.


Someone will be recommending you do not buy the extra memory from Apple but today’s prices are cheap compared to what I paid in 2009 so it still seems a reasonable option if you prefer Apple memory. If you go with another provider, just make sure they are reputable and guarantee the memory.

May 3, 2011 12:26 PM in response to Rick Lang

This is a brand new machine - it came out today-

When I owned a G5 they advised against unequal RAM.

It threw off the G5 and slowed down the computer.

DMS Memory has the two - 4GB RAM for a lot lot less then Apple.

If I buy from apple they will keep the two- 2GB RAM, so I will only have the two RAM chips I upgraded to.

If I buy the extra 2-4GB independent from Apple I will have 4 RAM chips, not just two RAM chips.

Rick Lang wrote:


Someone will be recommending you do not buy the extra memory from Apple but today’s prices are cheap compared to what I paid in 2009 so it still seems a reasonable option if you prefer Apple memory. If you go with another provider, just make sure they are reputable and guarantee the memory.

May 3, 2011 2:30 PM in response to woodie

woodie wrote:


This is a brand new machine - it came out today-

When I owned a G5 they advised against unequal RAM.

It threw off the G5 and slowed down the computer.

DMS Memory has the two - 4GB RAM for a lot lot less then Apple.

If I buy from apple they will keep the two- 2GB RAM, so I will only have the two RAM chips I upgraded to.

If I buy the extra 2-4GB independent from Apple I will have 4 RAM chips, not just two RAM chips.


The RAM management has changed since the days you purchased the G%. That used to be true but now what I told you is true. As long as the RAM is installed in a matched pair, you will get the full speed of the RAM for that pair; if you have two pairs of RAM, each pair need not be identical.


If you buy from Apple in the page where you configure your iMac, you have a radio button to select 4 GB or 8 GB or 16 GB and you are correct that then they keep the original 4 GB of RAM (of course they credit you with the price of the RAM they keep). But to get 12 GB in total, just leave the configuration ordered at 4 GB and then add to your order by buying the additional 8 GB RAM from the Apple Store memory page:

http://store.apple.com/ca/memorymodel/ME_IMAC_S11_27

May 3, 2011 2:43 PM in response to woodie

I would recommend buying the RAM from reputable vendors such as OWC (macsales.com) or Crucial; you have to remember that iMacs are extremely finicky about their RAM, so you will need to buy quality RAM. Both offer lifetime warranties; my preference is OWC - my 2010 iMac has a total of 12 GB (8 GB OWC RAM added) so I have 2 x 2 (stock) and 2 x 4 GB (OWC). I would not buy it from Apple because it would be more expensive; the last I heard they were using Samsung and Hynix as memory suppliers.


Edit: I've never heard of DMS - that does not necessarily mean anything, but I'd only go with highly recommended brands.


Second Edit: here are the prices for the RAM for new iMacs from OWC:


http://eshop.macsales.com/shop/memory/iMac/2011/DDR3_21.5_27


The prices there are just over $100 for 8 GB vs. $420 from Apple......

May 9, 2011 12:57 PM in response to woodie

Hey!


Just wanted to say thanks to woodie for asking and to Rick Lang and babowa for answering this.


I was confused about whether I could mix paired chips or not. But based on these response, I'm going to pick up the addl 8GB (2x4gb) and install it with my stock 4GB (2x2gb) for the 12 GB total. From what I understand, pairing like this shouldn't cause a speed hit, and will give the new machine more room to play, right?


Thanks again for making this easy!!

-Tony

May 9, 2011 3:27 PM in response to GryphonLA

I'm going to pick up the addl 8GB (2x4gb) and install it with my stock 4GB (2x2gb) for the 12 GB total. From what I understand, pairing like this shouldn't cause a speed hit, and will give the new machine more room to play, right?


Absolutely - that is what I've got in my mid 2010 iMac (the added 8 GB are from OWC).

Aug 9, 2011 1:00 PM in response to Thebestplacehere

I remonded get it from apple and if 16gb is a lot go for 12gb so 2x4gb,


Absolutely no need to get it from Apple. There is no Apple RAM - Apple uses third party/other manufacturer's RAM just like everybody else. Lately that is Hynix and Samsung, but that changes. So, unless you want to pay much more than necessary, buy it somewhere else. There have been problems with 16 GB reported; so the 12 GB recommendation is fine - as I posted before, that is what I have.

Aug 9, 2011 3:22 PM in response to babowa

Oh one question i post it in other two posts but no answer.

When i open my imac i saw that one of the plastic tabs the ones that you use to take out the modules one of them was with a corner like i saw the paper and is touching the memory module,can be problem if it become to hot,i mean can it be burn.

Do you know about plastic tabs damage or burn..

Thank you once again.

RAM Upgrade ? new iMac i5

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