crwdns2936637:0crwdne2936637:0 crwdns2853008:0crwdne2853008:0 crwdns2918746:0crwdne2918746:0
crwdns2918538:0crwdne2918538:0

crwdns2934243:0crwdne2934243:0 Oliver

crwdns2934249:0crwdne2934249:0:

http://support.apple.com/kb/HT5523
This lists the specifications that the RAM must comply with to be compatible.
http://support.apple.com/kb/HT5540?viewlocale=en_US&locale=en_US
This shows the procedure to upgrade the RAM.
The 27" and the 21.5" iMacs are different in that the 27" has a dedicated RAM compartment, accessible from the rear WITHOUT tearing open the screen.
Hope this helps!
+
+EDIT: To find out what RAM your computer will work with go to http://www.crucial.com/uk/systemscanner/
+and download the tiny application (Windows or Mac).
+After it's run it will send you to a webpage with an analysis of your computer and links to buy compatible RAM.

crwdns2915684:0crwdne2915684:0:

open

crwdns2934241:0crwdne2934241:0 Oliver

crwdns2934249:0crwdne2934249:0:

http://support.apple.com/kb/HT5523

This lists the specifications that the RAM must comply with to be compatible.

http://support.apple.com/kb/HT5540?viewlocale=en_US&locale=en_US

This shows the procedure to upgrade the RAM.

The 27" and the 21.5" iMacs are different in that the 27" has a dedicated RAM compartment, accessible from the rear WITHOUT tearing open the screen.

Hope this helps!

crwdns2915684:0crwdne2915684:0:

open