mixing memory speeds ddr3 1333 and 1666

[Carver]

Hello,

I have a ASUS motherboard set up with 12 gig of 1333. can I populate the other three with 1666? I am more concerned with stability than speed. Am I right in thinking manually setting all tyeh memory to the 1333 specs is best practice?

 

[sportsfanboy]

Yes you'll need to run your ram on the slower of sets rated speed and timings/voltage.

 

[jaquith]

Whatever you've got 'NOW' get more the 'SAME EXACT part numbered RAM.' Do NOT mix-match your RAM! Especially never mix: Speed, CAS timings, and Voltage. The typical difference between 1333 and 1600 MHz RAM is 1~3%