CPU/Mobo Kingston 2Gb DDR3 1333Mhz with Corsair 4Gb DDR3 1666Mhz

[matrix0683]

I just bought Corsair 4GB DDR3 1666 Mhz RAM, I also have my old 2Gb Kingston 1333Mhz RAM. Can I run both the RAM at 1333 Mhz or is it better to just run the Corsair RAM at 1666 Mhz. Would there be any compatibility issue or any noticeable drop in performance. I am a little confused.Please advise.

 

[dOm1naTOr]

Both will work fine.