4gb + 2gb

[docbrown]

Hi guys,

I currently have one stick of 4gb of corsair vengeance 1600 9-9-9-24 in my machine, and have been given a 2gb stick of mushkin silver line (same cas timings but 1333MHz)
Will I be able to use this alongside the 4gb stick without any problems?

Thx!

[kalniel]

Yes, if they're the same voltage and you're running both at 1333Mhz or lower.

[MrJim]

Yes, if they're the same voltage and you're running both at 1333Mhz or lower.

I think they may only run in single-channel mode though. I've got a feeling that only two DIMMs of the same capacity will run in dual-channel mode, although I could be wrong. As kalniel says though, the sticks will default to the speed of the slowest one.

[docbrown]

Thanks for the quick replys!

[kalniel]

I think they may only run in single-channel mode though. I've got a feeling that only two DIMMs of the same capacity will run in dual-channel mode, although I could be wrong. As kalniel says though, the sticks will default to the speed of the slowest one.

Given he's only running one stick currently I think single channel isn't a problem

(Incidentally, it's not always needed for the DIMMS to be the same size for dual channel either - depends on your system).

[MrJim]

Given he's only running one stick currently I think single channel isn't a problem

(Incidentally, it's not always needed for the DIMMS to be the same size for dual channel either - depends on your system).

I found this on wikipedia:

Modules rated at different speeds can be run in dual-channel mode, although the motherboard will then run all memory modules at the speed of the slowest module. Some motherboards, however, have compatibility issues with certain brands or models of memory when attempting to use them in dual-channel mode. For this reason, it is generally advised to use identical pairs of memory modules, which is why most memory manufacturers now sell "kits" of matched-pair DIMMs. Several motherboard manufacturers only support configurations where a "matched pair" of modules are used. A matching pair needs to match in:

Capacity (e.g. 1024 MiB). Certain Intel chipsets support different capacity chips in what they call Flex Mode: the capacity that can be matched is run in dual-channel, while the remainder runs in single-channel.
Speed (e.g. PC5300). If speed is not the same, the lower speed of the two modules will be used. Likewise, the higher latency of the two modules will be used.
Same CAS Latency (CL) or Column Address Strobe.
Number of chips and sides (e.g. two sides with four chips on each side).
Matching size of rows and columns.
Dual-channel architecture is a technology implemented on motherboards by the motherboard manufacturer and does not apply to memory modules. Theoretically any matched pair of memory modules may be used in either single- or dual-channel operation, provided the motherboard supports this architecture.

I hadn't heard of 'Flex mode' before...so with some Intel systems at least, the memory can be run in both dual-channel & single-channel mode.

[narz]

I've seen Flex mode during my bios boot up in the past (socket 775!) now I know why. My 2GB and 1GB ram sticks...

[DanceswithUnix]

I found this on wikipedia:



I hadn't heard of 'Flex mode' before...so with some Intel systems at least, the memory can be run in both dual-channel & single-channel mode.

AMD systems too, says the chap with 12GB of ECC ram in 3 sticks

Still get warnings in the motherboard manuals about matching sticks, but that seems to be more about stability than performance.