Don't bother with quad core now, unless your heavily into a app that supports it, the other two cores will just sit there idling, wasting power. If you decide to drop the quad then get a Asus Striker Extreme motherboard.
Raid 0 are you crazy? Get 3 (or more) HDD's and set them up for raid 5.
Drop the PhysX card, even the few games that do support it don't warrant the price (its only a few minor extra effects, no game has fully used its capabilities yet). Also any fps gains it gives for non-supported games are extremely small.
Stay with the single GFX card, upgrade later. I suggest the Asus EN8800 GTX.
You also didn't say what case you were going to use. The Gigabyte 3D Aurora 570 has everything you could ever want in a case.
Not to sure about the speakers, not aware of movies or games that support 7.1. So I say go with the M-Audio Studiophile LX4 5.1 (LX4 is 2.1 but you can get a expander "system" (upgrade) to get 5.1). And yeah go with a X-Fi Fatal1ty FPS as SgtH3nry3 said. Now that they got rid of the useless drive bay and remote it is more than $100 less than it used to be.
Note: as always I recommend this stuff based off the
Maximum PC magazine, great rag. They always try to come up with real world benchmarks and tests for their reviews instead of solely relying on spec sheets and benchmarking software (they do use them, but not only them).
