Mixing different type of dual channel memory

[AntiDogmata]

I have a PC with a Gigabyte GA-P67A-D3-B3 motherboard and a kit of 2x 2GB DDR3 1333mhz Kingston KHX1333C7D3K2/4GX (CL7 1,65v) on channel 1.
I now want to upgrade my memory to 8GB by adding an extra memory kit on channel 2.

My questions are:
Can I add a different dual channel kit (different mhz, different CL and different voltage)?

I was thinking about adding a RipjawsX - F3-12800CL9D-8GBXL kit
(I believe this is a 1600mhz CL9 1.5v dual channel kit)
I this compatible with my actual RAM and can I tune it to work at 1333mhz and CL7 latency?

 

[clutchc]

Yes you can. But any time you mix dissimilar memories, you run the chance of system instability. If you can tune the 1st pair to match the 2nd pair (or vice-verse), you will help improve your chances of success.

 

[Legohouse]

I have a PC with a Gigabyte GA-P67A-D3-B3 motherboard and a kit of 2x 2GB DDR3 1333mhz Kingston KHX1333C7D3K2/4GX (CL7 1,65v) on channel 1.
I now want to upgrade my memory to 8GB by adding an extra memory kit on channel 2.

My questions are:
Can I add a different dual channel kit (different mhz, different CL and different voltage)?

I was thinking about adding a RipjawsX - F3-12800CL9D-8GBXL kit
(I believe this is a 1600mhz CL9 1.5v dual channel kit)
I this compatible with my actual RAM and can I tune it to work at 1333mhz and CL7 latency?

Hello,

Well, 1600MHz is compatible. It is possible to mix different memory speeds and get them to work, that is easy with normal memory but not with advanced memory like RipjawsX. The good news is you can get them to work but you might have to play with the settings in BIOS or possibly go for a RMA. Also note when you mix higher speed with lower speed memory, the higher speed will default to the lower speed i.e, 1600MHz will run at 1333MHz when mixed with 1333MHz. Moreover, your CL will go higher that is from CL 7 to CL 9 (not a big difference but nonetheless that's a difference).