Memory Upgrade Question - Add to system memory or replace it?

[thedatapusher]

Quick question for the forums. I haven't upgraded memory in a long time, so maybe things have changed since my last trip to OWC.

We used to always replace ram instead of adding to it. Replacing with matched ram, same manufacturer, same size (4 x 4 = 16 or 8 x 2 = 16 not 8 + 4 + 4 = 16), same cadence etc. But looking at the current macsales page, it looks like they are saying to add their ram to the stock system ram pool not to replace it. What are the thoughts on this/common wisdom. What issues if any have been encountered.

Thanks all!

 

[Intell]

If the memory is the same speed and kind, add to it. If they are different sizes, you can add to it but you won't gain maximum memory throughput by doing so. Under some circumstances you can mix memory speeds, but that is best avoided unless you know what you're doing.

 

[thedatapusher]

One would assume then that you would need access to the system prior to ram purchase to make that determination. Unless they send one kind of ram in the 3.4GHz 27" iMac... End tax year purchase...

 

[Intell]

They don't need to be the same manufacture, just the same kind. If you know what model the iMac is, just look up its specifications to see what kind it takes and order some of that kind.