This Memory with this Board?

mace200200

Honorable
Okay, my main question is, why are there 3 different PC speeds for 1333MHz RAM? Will the kind I picked (the fastest kind) work alright with this board?

I was asking about boards the other day, I've decided to spend some extra money for the Gigabyte-970a-UD3, since I'm most used to Gigabyte brand boards. Looking at memory, since I run 4Gigs of DDR2 currently (32 bit OS), don't run multiple programs, and I'm not an OCer I plan to save some money now and just buy 2x2Gb sticks running @1333 Mhz (I don't want to mess with timings and stuff in BIOs), like I said, I don't OC so adding two more sticks for 8 gigs later won't bother me, I'm switching to a 64 bit OS.

Board: http://www.newegg.com/Product/Product.aspx?Item=N82E16813128519
RAM: http://www.newegg.com/Product/Product.aspx?Item=N82E16820231276 (this memory because it has the lowest CAS LAT and Timings compared to other RAM for the same price)
 

mace200200

Honorable
I'm aware that the 1600Mhz RAM is pretty much the same price, but I don't want to have to set it manually in BIOs. I'm not sure how to do it, and when I get my new board I'll be anxious to get windows installed and licensed and running right. And I'd think that the CL LAT 7 would make up for it a bit.

Is there any reason there's three different kinds of 1333 MHz ram though?