4 GB dual channel at 1600 MHz or 8 trip. chan. at 1033 MHz?

jn865

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Dec 6, 2011
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Hello,

I'm not too familiar with how RAM works in regards to channels and speed. Right now I have 4 GB of DDR3 1600 MHz dual channel RAM from Corsair. I have a friend who is getting new RAM and wants to sell me his old RAM which is 8 GB of generic RAM which is triple channel but only 1033 MHz. He wants a cheap amount for it and I am thinking about purchasing it, but I just want to know if I'm lowering my possible performance by going from 1600 MHz to 1033 MHz.

All information is appreciated.

Thanks
 
Solution
I'll tell you right now 8GB isn't possible for a tri channel kit. to get 8GB with three modules one would need to be a 4GB module and the other two would be 2GB modules (for a three module kit) or two 2GB modules and four 1GB modules. In either case they aren't all from one kit. Also most motherboards don't support tri-channel RAM so you would need an x58 system for tri channel capability.

Suggesting you have an x58 system, I would expect the performance to be extremely close between dual channel 1600 and tri channel 1033. There may be a hundredth of a percent drop because the bandwidth of tri 1033 is very slightly lower (compare 25600 maximum theoretical to 24792 maximum theoretical)

In either case it won't be much better than...
I'll tell you right now 8GB isn't possible for a tri channel kit. to get 8GB with three modules one would need to be a 4GB module and the other two would be 2GB modules (for a three module kit) or two 2GB modules and four 1GB modules. In either case they aren't all from one kit. Also most motherboards don't support tri-channel RAM so you would need an x58 system for tri channel capability.

Suggesting you have an x58 system, I would expect the performance to be extremely close between dual channel 1600 and tri channel 1033. There may be a hundredth of a percent drop because the bandwidth of tri 1033 is very slightly lower (compare 25600 maximum theoretical to 24792 maximum theoretical)

In either case it won't be much better than single channel performance because CPUs, unlike GPUs, just refuse to utilize anywhere near the maximum theoretical bandwidth of a memory system.

Memory isn't a bottleneck on any modern CPU except for AMD's LIano series, and even then it's only because of the insane integrated GPU of LIano.
 
Solution
Its the motherboard that will indicate whether its dual or triple channel. The memory sticks individually are all single channel until they’re matched in pairs or tripples.

1x 2gb = single channel
2 x 2gb = dual channel
3 x 2gb = triple channel

Computer shops market memory in bundles of dual/triple to make it easier on the consumer and less hassles with incompatibly problems.

There will always be compatibility risks when matching different ram sizes and brands. Its also not a sure thing your motherboard will even accept the generic ram as well, also another risk.
 
Thanks for all the replies. I knew deep down inside I shouldn't get it since it is just generic RAM. Since this RAM is going into my "gaming PC" I don't really want to stick no name equipment into it.

Thanks again