DDR 3 and AMD motherboard compatibility

[Wheelzup]

I'm going to be building a new AMD based system and I've been looking at boards and memory for the CPU that I plan on using an AMD Phenom II X6 1090T Black Edition. The board I've decided to use with it is an MSI 890FXA-GD70. Now I'm stuck on what RAM to add to the system. In the boards specs it says it can run the following: DDR3 2133 (O.C.) / 1800 (O.C.) / 1600 (O.C.) / 1333 / 1066 I'd like to have at least 8GB of RAM for this build. It will pull double duty as a work and play system. I've looked at each of these pieces of RAM and from what I've read both online and in a couple of magazines that with this particular CPU that I should look for memory that is designed with AMD boards and CPU's in mind. I'm looking for suggestions and have one question about the speed of memory, the question is if for example I purchased DDR 3 2000 would it dummy down to 1800 or slower so the system would boot without any trouble, or if I went up to the 2133 would it do the same? If I would choose 1600 can it be over clocked to reach 1800 or better? The reason I'm asking is there seem to be many more choices with DDR 3 2000 and DDR 3 1600 than the DDR 3 1800 and most of the DDR 3 2133 are meant for Intel based systems. The MSI board is also a dual channel board which does make a difference when it comes to the kits.



It's been a long time since I've done a build which is AMD based and could use some input.

 

[Yellowbeard]

Based on what I have seen and read, 1600 is the "sweet spot" for AMD these days. You can go faster, depending on your CPU/IMC, but at the expense of latencies. 1600C6, C7, or even C8 is all you really need to get a great OC and great performance.

 

[Wheelzup]

In general then the lower the latency the faster the RAM? I do plan on speeding up the CPU and I am thinking about water cooling with one of the Corsair kits. They have gotten very good reviews and since I'd be new to it the simpler the better.

 

[Yellowbeard]

Yes, lower latency is better in general.

 

[Kuzi]

Hello Wheelzup, I've built a system a few months ago based on the excellent MSI 890FXA-GD70. It's a quality mobo and the BIOS has all the settings for tweaking and OCing that you can think of.

I wanted 8GB low-latency memory for the system, so I bought Corsair Dominator 8GB (4x2GB) (CMD8GX3M4A1333C7), they are rated at 1333MHz 7-7-7-20 and have AMD Black Edition Memory Profile (BEMP). I'm only running them at stock for now, but I'm sure they can do 1600MHz with maybe some losser timings and/or higher voltage. The only drawback I see here is that they take up all 4 slots of the board.

You can find this RAM below:
http://www.newegg.com/Product/Produc...82E16820145284

It's slightly pricey, but you get what you pay for. I haven't got a single crash since building it three months ago, OS used is Windows 7 64bit Professional. About the memory clocks, lets say if you compare 1333@7-7-7 or 1800@9-9-9, the difference in performance is really minimal, and I'd say it's not really worth the effort. I know some people will disagree