I got two sets of these to upgrade my gaming PC to 32GB of RAM. At first they wouldn't run as my ASUS P8Z68 Deluxe/GEN3 needed a BIOS upgrade, but as soon as I upgraded to the latest version of the BIOS for my system (3304), everything on this RAM worked great - so chalk that up to an archaic BIOS. Once that was done, I was hitting the 1600 speeds I should see normally. Performance has been great, hitting the top level on the Windows scores. Very happy with it, the chips aren't too huge (even though those fins on the heatsinks look like they are,) people with small cases might want to beware, they are rather tall.