Can I mix memory modules?

Hi Ron,

Simple answer is NO you cannot mix modules. iMacs are notoriously sensitive to their memory...must match the specified memory in rating, though not size. You can see more about the memory limits at:

http://support.apple.com/kb/HT3011

Mixing speed and memory chip classes does not work with Macs.

You cannot put the 800 in place of 667 as the machine will not start, or if it does will have kernel panics.

The laptop modules should work, you can try and see.

Hope this helps.
Ralph

Message was edited by: Ralph Landry1

Finally, is there any risk in trying any of the above?

Usually if the Mac cannot use the RAM it just does not pass the Power-On Self-Test, you do not hear the startup chime (your sign it failed the test) and the Mac does not startup.

Or it starts up, experiences a kernel panic and shuts back down.


Dah•veed

Thank You for extending the courtesy of awarding to comments that are helpful or provide answers in the Apple Discussions, as this is not mandatory, but it is much appreciated!

You're very welcome, and thanks for the positive feedback, we all appreciate it.

I am buying my first iMac, 27 quadcore, I want to upgrade the memory and ive been reading an immense number of reports on problems with memory configurations. Is there a simple answer? I want at least 8gb, 16gb would be very nice. Can someone direct me to the best choice for memory configurations? 12 gb vs 16gb? brand? I am simply leaning towards getting 12 gb from newegg to avoid the 16 gb issue.

Teufelhunden,

Hi I know you're new so let me try to educate you a little. First is trying to ask a question in someone else's thread is considered rude, it's called thread jacking. I'm sure that wasn't your intent though. Next is if you see a green star by a thread that indicates it has been answered so posting a question in a thread that has already been answered probably isn't even going to be looked at.

I would recommend opening your own thread and I'm sure you will get some people more than willing to answer your question. If I see it I'll help you too! If you need assistance on how to create a thread click above where it says "Expanding your Intel-based iMac" and then you will see a link called *Post new Topic*.

Regards,

Roger

thanks