DDR3 1866mhz on GIGABYTE GA-870A-UD3?

[moabak]

I'm building with a GIGABYTE GA-870A-UD3 AM3 AMD 870 SATA 6Gb/s USB 3.0 ATX AMD Motherboard. (And a AMD Phenom II X4 955 Black Edition. And an entry level Radeon HD 5570 1GB video card.) The ram description on the mother board says:

"DDR3 1866(OC)/1333/1066 *To reach DDR3 1866MHz or above, you must install two memory modules and install them in the DDR3_3 and DDR3_4 memory sockets."

1) Can I use 2000mhz ram or does it have to be 1866mhz exactly?
2) How big of a difference am I going to see between 1333mhz and 1866mhz? On a non gaming business machine running three monitors and multiple apps?

The reason I ask is financial. 1333 ram is cheapest. 2000 ram is next expensive. And 1866 more expensive than that.

Thanks in advance for any help. Greatly appreciate these forums.

PAtrick

 

[saint19]

1- Not really, you can use even a 1333MHz RAM and overclock it to 1866.
2- That depends of RAM's timings.

 

[moabak]

How do I figure out how fast my ram is working? I have CPU-Z installed. And then how do I change it if it's not running at 1866?

 

[saint19]

Open CPU-Z and select the memory tab, then you can see "frequency", take that number and multiply it by 2 (dual channel)