For testing today we used the excellent ASRock P67 Fatal1ty Profess1onal motherboard (yes, the ‘1's are intentional).
We found that the ASrock Fatal1ty bios automatic settings enabled 1600mhz, but by manually forcing the XMP profile ‘1' setting, the board correctly adjusted them to 2,133mhz with a 1T command rate, CAS Latency of 7, RAS TO CAS Delay of 10 and a Row Precharge time of 27.
System validation can be viewed over here.
The Windows 7 Experience Index gives the memory a maximum score of 7.9 (ignore the graphics results, no driver was installed for testing).