New build for Aussie gamer

Im basically looking at upgrading my AMDx2 system to an Intel quad over the next couple of months. Havnt used intel for a long time wouldve prefered to stay with AMD so im guessing id be best of with a i7 quad. Will be mainly using it for Gaming (mainly fps) and surfing the net. Quite often have alot of apps running at the same time extracting, encoding, watching a movie all at the same timer. I have a lot of stored data and a raid backup setup for the most important stuff may be worthwhile for me.

APPROXIMATE PURCHASE DATE: in the next 2 months will buy parts over time

BUDGET RANGE: $400 - 600 mobo $300 ram $400-600Cpu

SYSTEM USAGE FROM MOST TO LEAST IMPORTANT: Gaming, surfing the internet, watching movies, minor video encoding

PARTS NOT REQUIRED: OS, GRAPHICS CARD have 2x gtx285 2gb ,Case

PREFERRED WEBSITE(S) FOR PARTS: whatever has the best price

OVERCLOCKING: Yes Maybe SLI Yes

ADDITIONAL COMMENTS: Will buy http://www.pccasegear.com/index.ph [...] ts_id=8802

Already have 2x GTX285 2GB , 4x 1tb hardrives, monitor, mouse

Ive had a look for motherboards and come up with these three
Gigabyte GA-EX58-EXTREME
http://www.pccasegear.com/index.ph [...] ts_id=8471

EVGA X58 Classified E760
http://www.pccasegear.com/index.ph [...] s_id=11356

ASUS Rampage II Extreme
http://www.pccasegear.com/index.ph [...] ts_id=8523

Im leaning toward the Gigabyte as ive used there boards for the last 2 builds ive done.


Also looking at getting this for audio/video playback
ASUS Xonar HDAV1.3 Deluxe
http://www.pccasegear.com/index.ph [...] ts_id=8802

Not sure what the best ram and Cpu would be as i generally wouldn't even think about building an Intel system so any help or suggestions would be appreciated.

Thanks

so this cpu not too bad off a price
http://www.pccasegear.com/index.ph [...] ts_id=8485

and this must be the ram
http://www.pccasegear.com/index.ph [...] s_id=11367

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and what bout this cooler

CoolerMaster V10 Hybrid TEC
http://www.pccasegear.com/index.ph [...] ts_id=8849

ok i found the board u mentioned and ill have to decide between that and the Gigabyte GA-EX58-UD5.

out of the coolers i found id go the scythe