Why would someone get 3GB of Ram?

[Sun Baked]

There is some architectural issue that prevents the system from being able to address memory beyond 3GB. So if you install 4GB, you will still effectively only have 3GB.

Apple has already stated that this will happen.

So you might as well put in 3GB and save some money, unless you really want to spend all that money to see if dual channel is still possible -- even though you are limited to 3GB.

Likely it'll be quite an expense at the moment for a nominal real world benefit. Of course the brag value alone is so worth it.

iMac (Late 2006): Memory Specifications

Note: If you do install a 2 GB SO-DIMM in both the bottom and top memory slots of the computer, the About This Mac window and Apple System Profiler will both show that you have 4 GB of SDRAM installed. However, Activity Monitor and other similar applications will reveal that only 3 GB of SDRAM has been addressed for use by the computer.

 

[rgbmaster]

What's the best place to get memory for the imac 24" online? What about brand? Crucial or Samsung? Or it does not matter?

 

[generik]

These new iMacs are really 32 bit computers

 

[Sun Baked]

These new iMacs are really 32 bit computers

64-bit registers, 48-bit virtual memory, 36-bit physical memory, in a 32-bit chipset.

But it is the 32-bit chipset that is biting us in the ass.