DDR3 compatibility puzzle

[momist]

I'm hoping to build a system using an Asrock FM2A75M-DGS and AMD A8-5600K. I've been offered two G.Skill 8GB Single Channel memory kits F3-1600C11S-8GNT. These are listed on Amazon, but the description baffles me. If they are single channel, why are they described there as "Dual Channel DDR3 1600"? I thought that dual channel memory needs two identical units, which is what I've been offered. The listing on Amazon also says "XMP Ready for 1st, 2nd and 3rd Generation Intel Core Processors. Compatible with AMD platform." and a reveiwer says he had to turn XMP on in the BIOS. This won't be there on the Asrock MB. Will it work?

Edit: This site: http://www.memoryc.com/computermemory/ddr3ram/8gbgskill1600mhzpc312800ntseriessinglemodulecl11.html suggests that it can be used in dual channel mode with two matching units, and that it is PC3-12800 RAM.

 

[Pinhedd]

I'm hoping to build a system using an Asrock FM2A75M-DGS and AMD A8-5600K. I've been offered two G.Skill 8GB Single Channel memory kits F3-1600C11S-8GNT. These are listed on Amazon, but the description baffles me. If they are single channel, why are they described there as "Dual Channel DDR3 1600"? I thought that dual channel memory needs two identical units, which is what I've been offered. The listing on Amazon also says "XMP Ready for 1st, 2nd and 3rd Generation Intel Core Processors. Compatible with AMD platform." and a reveiwer says he had to turn XMP on in the BIOS. This won't be there on the Asrock MB. Will it work?

Edit: This site: http://www.memoryc.com/computermemory/ddr3ram/8gbgskill1600mhzpc312800ntseriessinglemodulecl11.html suggests that it can be used in dual channel mode with two matching units, and that it is PC3-12800 RAM.

There's no physical or electrical difference between memory modules that are sold in single, dual, triple, or quad channel kits. Kits simply contain DIMMs that have been tested to work together in that configuration.

You could buy two individual sticks (preferably identical) and install them on different channels, they will run in a dual-channel mode of operation.

You could buy a set of two matched sticks and install them on the same channel, they will run in single-channel mode of operation.

There are a few constraints though:

1. All DIMMs in the entire system must be run at the same DRAM IO bus frequency. While it is possible to mix modules of different marketed speeds, only the lowest common speed will work.

2. All DIMMs on each channel will receive the same supply voltage. X79 motherboards can provide a separate supply voltage to different channels (AB/CD)

 

[Tradesman1]

A little food for thought, for what it's worth, these are 1600 --- CL11 sticks (very slow, entry level is considered 1600 - CL9, can do better performance wise with 1333/9 or 1333/8.

Also the APUs aren't as powerful as a regular CPU and really prefer faster DRAM than even 1600 or 1866, so with these may well see a lot of bottlenecking and overall slow performance

 

[momist]

A little food for thought, for what it's worth, these are 1600 --- CL11 sticks (very slow, entry level is considered 1600 - CL9, can do better performance wise with 1333/9 or 1333/8.

Also the APUs aren't as powerful as a regular CPU and really prefer faster DRAM than even 1600 or 1866, so with these may well see a lot of bottlenecking and overall slow performance

Thanks for the advice Tradesman1, I'm not a gamer and trying to build to a budget. I've got these two identical RAM sticks at a very low price, so I'll give them a go. The result, with Linux and 16GB, has to be better than my current setup where the bottleneck is only having 2 GB DDR and an old dual core Athlon.

Thanks Pinhedd for confirming what I thought I knew about how the memory is used, Amazon does confuse the details very often.

 

[Tradesman1]

Let us know how it goes!