1204. I did have some issues getting it going at first. It wouldn't post with 4 sticks. I then removed my PERC5i card from the x4 slot and it posted. I got all the settings configured and then put the PERC5i card back in and it posted with no issues. Haven't had any issues since. Just an FYI, my voltage settings for VCCSA (.90v) and VCCIO (1.0v). DIMM voltage had to be set to 1.55v before it was stable at the XMP profile with 4 sticks.