First build - ram and gfx questions

[fuzg13z]

Hey folks! I'm in the middle of my first build, I'm taking it slow and purchasing the parts as they come on sale and as I can afford them. So far I've purchased:
Case: Antec 1100
PSU: OCZ Z-series 1000 watt 80+ gold cert.
Mobo: ASRock Extreme4 LGA1155

Parts I'd like to purchase:
RAM: ??
Video Card: XFX DD Black Edition 7950 -or- Sapphire 7950 OC
SSD: OCZ Vertex 4 128gb
HDD: WD Caviar 2TB Green SATA 3
Proc: 3570K
CPU cooler: Noctua DH-14

My intentions with this rig are solely gaming. I'd like to be able to run all games on maxed out settings at 1980x1200. Eventually I'll probably add another 7950 and do a 3 monitor 1980x1080 IPS setup. I play WoW and BF3 and of course I'll be checking out lots of other games as they hit the shelves. I'm not really sure what's required for my ram though. My board is dual-channel but I'm not sure which frequency I should get; 1600? 2400? Somewhere in between? I'm trying to be fairly conservative with my money so I don't want to spend a fortune. As I understand 2400 MHz ram is only beneficial in memory intensive apps like graphical rendering. Since I only intend to be using this rig for gaming, I'd like to know how much (if any) of a performance gain I'd get.

Also regarding RAM, I've got a question about the nomenclature; what do the 4 numbers separated by hyphens mean?

Another question I've got is in relation to the video cards. Both of these cards are OC version cards; does this just mean that they take the reference board and change its CMOS settings to OC it? Or does it mean that there are actual physical changes to the board that allow it to be further OCd than the reference design? As my system ages and can't run all games at max I'll likely OC both my graphics card and my proc so if I can squeeze more OC headroom out of my gfx card by buying one of these OC versions than I think it's definitely worth the extra $40. However, if it just comes with pre-adjusted CMOS settings then why would I pay more for something I can do myself??

Thanks in advance folks.

 

[C12Friedman]

I'd say go with Corsair Vengeance 1600MHz ram
http://www.newegg.com/Product/Product.aspx?Item=N82E16820233186
The four numbers, 9-9-9-24 in the case of the Vengeance ram, are latency numbers and basically represent how many cycles of delay before returning data. That's overly simplified, here is a good article for further info...
http://www.hardwaresecrets.com/article/Understanding-RAM-Timings/26/1
Graphics cards, in most cases (not all) non-reference graphics cards are not built on the same PCB's as reference cards and the location of certain elements (GPU itself) are in non standard locations on the card. Usually in the case of overclocked graphics cards, the cooling system is beefed up well beyond reference specs. The "black edition" cards are normally from better binned parts.

 

[fuzg13z]

Hey I appreciate the quick response C12Friedman. The article was very comprehensive!

 

[fuzg13z]

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