Does 945PM async dual channel?

I have a friend with an inspiron 6400 (945PM) chipset currently running 1GB (2x512GB). I have a spare 2GB module, if I replace one of the 512's with a 2GB will it work in dual mode still? Or should I just take both 512's out and run the single 2GB stick?

 

It'll still run dual channel. Not that dual channel really provides any tangible benefits in practice...

 

Hello, the 945PM supports both Symmetric and Asymmetric dual channel mode. Symmetric dual channel is the highest performance mode, but it requires both channels to have equal amounts of memory. Asymmetric dual channel allows some flexibility by allowing different sizes for both channels.

So you have 3 options:

Symmetric Dual Channel
1GB=2x512MB

Asymmetric Dual Channel
2.5GB=2GB+512MB

Single Channel
2GB=Single 2GB stick

If we ignore RAM capacity for performance comparisons, the relative performance in order from highest to lowest is: Symmetric Dual Channel->Asymmetric Dual Channel->Single Channel

The worst option is the last option. The decision will come out to be based on what your friend does. If he doesn't run anything intensive and run XP, Option 1 is the best. If he runs Vista, and does anything intensive on his laptop he might actually benefit from running Option 2. Still not completely attractive, but if the way he uses his laptop uses a LOT of memory, Option 2 might be the best.

 

What said above is correct. Additionally the 945 chipset will only be able to recognise 3GB of ram whether you use 32bit or 64bit as that is the chipset limitation. So if you mate wants to max out is computer he will need a 2GB and a 1 GB module running is assymetic channel. He could put 2x2GB in as cost is so low to make it worthwhile to get the full 3GB running symmetric

 

I don't think this is true. I'm fairly certain the 945 should be able to take 4GB given that the BIOS is properly implemented, etc.

 

Don't really worry about asymmetric dual channel. It is single channel with a little boost every now and then. Especially with a 512MB module and a 2GB module, it will rarely access both channels simultaneously.

 

I always thought they were limited to 2gb. My friend has both a Dell Mini 9 and Dell Mini 10v, and he says that max ram support is 2gb. Both have the GMA950 integrated cards

 

The 945 chipsets used in the Netbooks use a modified 945GSE for lower power. The higher end 945GM and PM chipsets can support more memory.

Update:

945GM/PM: 4GB
945GMS/945GSE/940GML/943GML: 2GB
945GU: 1GB(specialty chipset used in the Dothan-512 CPUs for UMPCs)

 

The BIOS is the limiting factor. Even on 64 bit, I do not get full 4GB of memory.
I have the E1505/ same as Inspiron 6400.
On XP X-64 I get 3.1Gb of memory recognized, just as much as I do on a 32 bit operating system.

K-TRON