Mixing memory

At the moment I have 2x2gb Crucial Ballistix PC3-12800 1600mhz for a system I have yet to build...(waiting on B3 revision Asus P8P67 Deluxe board, I7 2600)...While waiting for this recall to play itself out I found crucial now has 2x4gb Ballistix PC3-16000 2000mhz.
Question is, can these two types of memory be combined without any problems on this board? Any help would be appreciated.

You could loosen the timings to fit the lowest CAS one. Example :
( im just throwing in numbers here, i do not know the specific timings of your ram sticks )

1st set of ram : 8-8-8-24
2nd set of ram :9-9-9-28

Loosen the CAS timings of the first set of ram so it matches the 2nd one. So it will be like this :


1st set of ram : 9-9-9-28
2nd set of ram :9-9-9-28


Downgrade the 2000Mhz to 1600 and you should be good to go.

Keep in mind that combining different types of ram is not ''recommended'' but in your case, its the same brand, so I guess you will have no problem.

Ah, and

Mixing RAM isn't guaranteed to work, but if you want to try, do like Volumetrik said. Set the loosest timings, lowest speed, and also the highest voltage. Here's another example:

Have these two sets:
1600MHz 7-8-7-24 1.5v
2000MHz 8-9-8-20 1.65v

Use these settings in the BIOS:
1600MHz 8-9-8-24 1.65v

That answers the question, guess I can keep the 2 gig sticks after all.

FYI...Here are the latencies of the ram, guess I should have entered them in the original post... 2x2gb 1600mhz: 8-8-8-24
2x4gb 2000mhz: 9-10-9-24

Thanks for your help!