Last Questions before Purchase/Build

I will be using this MOBO

EVGA E758-A1 3-Way SLI (x16/x16/x8) LGA 1366 Intel X58 ATX Intel Motherboard
http://www.newegg.com/Product/Prod [...] 6813188039

I will be using the Superclocked GTX 275 as my GPU
http://www.newegg.com/Product/Prod [...] 6814130478

i have a few questions?

what is the IDEAL RAM i should use for this, i am going to be placing my order hopefully within 24 hours and would like RAM i can just pop in and go with.....links would be awesome

I am using this MOBO because i do plan on using SLI in the future, just not at this very moment, as time progresses and I am able to save up some more money to buy more cards.

one more question, when in fact i do begin to use SLI, do the graphic cards have to be identical?? if so is the GTX 275 a good one to use?

the rest of my machine i already have all figured out, waiting in the shopping cart on newegg, just need to figure out the correct RAM i should use.

Build
i7core 920
Mobo listed above
Superclocked GTX 275
Western Digital Caviar Black WD6401AALS 640GB 7200 RPM 32MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive (2 of these)

CORSAIR CMPSU-750TX 750W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified

Tuniq TX-2 Cooling Thermal Compound - Retail

XIGMATEK Dark Knight-S1283V 120mm Long Life Bearing CPU Cooler

XCLIO Windtunnel Fully Black Finish 1.0 mm SECC Chassis ATX Full Tower Computer Case
http://www.newegg.com/Product/Prod [...] 6811103011

ASUS VH226H Black 21.5" 2ms(GTG) HDMI Widescreen 16:9 Full HD 1080P LCD Monitor 300 cd/m2 1000:1
http://www.newegg.com/Product/Prod [...] 6824236051

Samsung SH-S223Q 22X DVD R/W burner with LightScribe

Windows 7 64 bit

so thats it, hopefully you can give me some advice on RAM, and opinions on the cooling/ventilation i will have going on, and if i do need more of that

THANK YOU ALL SO MUCH FOR YOUR ADVICE IN CHOOSING PRODUCTS! YOU HAVE HELPED ME TREMENDOUSLY, I COULD NOT HAVE DONE THIS WITHOUT EVERYONE'S HELP ON THIS BOARD

thank you for the speedy reply, i had been contemplating that memory so i went ahead and added that, as well at the Gigabyte board, wondering if i should just go with the UD5?

http://www.newegg.com/Product/Prod [...] byte%20ud5

as for the case. i like to have a little bit of flash any other cases anyone would recommend with good cable managemnt, good space, good cooling, and a bit of flash?

also the opticals everyone recommends, the Samsung SH-S223Q and the LG One have been out of stock for the last 7 days or so, any other ones people would suggest? I am looking to order this before the weekend