Will 2*2GB and 2*4GB sets of dual channel RAMS work?

Question

I intend the following setup :

• Slot 1 (Black ): UDIMM 2GB ADATA DDR3-1333 1.5V 9CAS AD3U1333C2G9-R
• Slot 2 (Yellow): DIMM 4GB ADATA DDR3-1333 1.5V 9-9-9 AD3U1600W4G11
• Slot 3 (Black ): UDIMM 2GB ADATA DDR3-1333 1.5V 9CAS AD3U1333C2G9-R
• Slot 4 (Yellow): DIMM 4GB ADATA DDR3-1333 1.5V 9-9-9 AD3U1600W4G11

Motherboard : Asus B85M-G

Reason for such a setup: I have one 2GB Ram and wish to upgrade. 2*4GB has maximum Value for money. So plan to purchase that. I wish to use existing 2GB, so plan to purchase another 2GB.

Doubt :

• Will there be any issues?
• If not, will I get the the result of two dual channel setups? (One 2GB dual channel and one 4GB dual channel)
• If I have only 3 RAMS (Two 4GB and One 2GB), will I get better overall performance if i avoid the 2GB RAM?

Answer 1

Will there be any issues?

Probably not.

There are no generic reason why it should not work, though some motherboards have had weird issues. In general try if you have a no name motherboard then everything will work. If you have a brand motherboard (like Compaq, Dell or HP) then those tend to be incompatible with the generally accepted standards.

If not, will I get the the result of two dual channel setups? (One 2GB dual channel and one 4GB dual channel)

Yes. 2x2GB and 2x4GB should allow dual channel access to both sets of DIMMs.

If I have only 3 RAMS (Two 4GB and One 2GB), will I get better overall performance if i avoid the 2GB RAM?

It depends.

If you have a single program using a limited a amount of memory then 2x4GB in dual channel mode is often 1% to 10% faster. If you have programs (and OS dis buffers) using more then 4GB then 6GB will be faster.

See also:

• Is it better to have 4GB RAM in dual channel or 6GB as single channel?
• Help with RAM speeds? and Is dual Channel worth it?
• One 8 GB DIMM vs two 4 GB DIMMs in dual channel mode

And a few others. Temped to flag it as duplicate off one of these.