I'd like to expel a few myths to the OP at this point in time since he is a new first time system builder
1) SLI and Crossfire are pointless and a waste of money, don't bother. Parallel processing modes do not distribute jobs, they just create more bandwidth, and your overall performance increase will be nil to very little and in some cases it performs less if it isn't coded for it.
2) RAID 0 - again another pointless technology that gamers like to use. RAID only really help with pure throughput of data. It does not increase your FPS or anything else, and it makes your system way less stable. Don't bother, just get a nice high speed hard drive like a Raptor.
3) When people say that one video card gives a 10% performance increase over another it is extremely subjective and benchmarks never reflect real world performance. Always go for the best product for your dollar in my opinion because in your build you may only get a 5% increase, or it could be 15% or whatever. So, my advice is always get the best for your dollar.
4) DX10 is not needed and it actually performs worse. The plus side to DX 10 is that it looks a bit prettier, this is just an FYI.
5) 64 bit OS system drivers suck, just a warning
6) Dual core versus Quad core - this is hard to say. Not everything fully supports 4 cores, however a quad core should technically multi task a lot better over a dual core. This is subjective and would require some research. I think one of the better processors at the moment for the dollar is the Q6600 by intel.
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115017
7) Don't ever go cheap on a powersupply or motherboard and this goes back to buying the best for your dollar as well. Your motherboard is the backbone of your system and your Power supply supplies power. Cheap power supplies can cause performance issues, burn out and damage your system.
8) Always get a 2nd opinion. Google is your friend. Research your products, and read user reviews. A lot of times the idiots that buy from newegg.com will give a product a bad review for the dumbest reasons. Like the return policy wasn't that good, or they didn't like the size of the card, or it didn't over clock that well. If you don't over clock then why would that matter to you?
9) Don't bother over clocking, again this is highly misunderstood and doesn't really raise performance. Sure you can pump more data through your processor but you can also create bottle necks and lessen the stability of your system over all. Its like putting NOS in a car, those engine blocks aren't bullet proof and if you run it all the time there is bound to be a malfunction. Stable systems are generally ran at factory clock speed, because they are designed to execute instruction sets at the most optimal possible speed, with zero to a very small rate of failure. Increasing the speed increases the rate of failure. Also, over clocked RAM and the like are marketing schemes. Benchmarks do not reflect real world performance and remember always get the best product for your dollar.
10) This is the most important thing...Don't be afraid to ask dumb questions. Everyone has to learn at some point and you are better off just asking than blindly going through trying to figure something out.
Good luck
