Possible to run 6GB (2x1 and 2x2) in dual channel?

[Talon]

A while back I bought another 4 gigs of memory for my computer (a Corsair XMS2 2x2GB set) and installed it alongside my existing 2 gigs (a Corsair XMS2 2x1GB set).

I just noticed on POST that it was detecting the memory in single-channel mode, figured I had mistakenly installed it in the wrong slots and swapped them from 1122 to 1212. However, the memory is still registering as running in single-channel mode.

Is it not possible to run dual-channel with four memory modules that are different sizes, even though each module has a corresponding module of equal size? If it is possible, what am I doing wrong?

My motherboard is an Asus M2N32-SLI deluxe.

 

[Talon]

I downloaded the motherboard manual and it states that:

For dual-channel configuration(2), you may:

Install identical DIMMs in all four sockets OR
Install identical DIMM pair in DIMM_A1 and DIMM_B1 (yellow sockets) and another identical DIMM pair in in DIMM_A2 and DIMM_B2 (black sockets)

The second setup is the one that fits my scenario and is the configuration the memory was originally in and what I've switched it back to, but it's still running in single-channel mode.

Either DIMM pair installed separately runs in dual-channel mode.

 

[Mike Clements]

Mixing memory is always hit or miss. How are you determining if your system is running dual channel vs single?

 

[Talon]

The motherboard displays memory mode (dual- or single-channel) during POST along with the bus speed and available size.

 

[Mike Clements]

Check it in the OS using CPU-Z.

 

[Talon]

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