Hi I installed four Corsair Value Select SO-DIMM DDR3 PC10600/1333MHz CL9 4GB CMSO8GX3M2A1333C9 in my 2011 i7 iMac. After i installed the memory i tried to run AHT without any success. The computer freezes before AHT starts to test the computer. I have also run Memtest 4.22 which it passes without any problems. Edit: The stock ram works just fine in AHT and Memtest. Any ideas why AHT fails to start at the same time as Memtest sais that the corsair memory is OK? Is AHT just picy with ram or is the ram faulty?