Mixed cas latency speeds

[mpainter]

I am currently running F3-10666CL8D-4GBHK 2X2gb running at 8-8-8-21 in my system. I am thinking of buying F3-10666CL9D-8GBRL 2x4gb to bring my system to 12gb. However the new ram runs at 9-9-9-24-2N. Will this cause any conflicts between the two speeds of memory or is it nothing to worry about?

[GSKILL TECH]

It is possible that the two kits can not work together. Especially with dual channel motherboards, it can be difficult for 2GB and 4GB sticks to work together.

Thank you
GSKILL TECH