Here is what I'm building after reading and learning a bunch from several sites, including Toms and Newegg.
Mobo: MSI K9A2 Platinum
CPU: AMD Phenom Quad 9600 Black Edition (Plan on OC to 2.6Ghz as that seems to be the fastest safe speed)
Cooler: Zalman CNPS 9700
Mem: 8Gb of OCZ SLI Ready Edition
PSU: Corsair 750W Heavy Duty
Gfx: MSI NX8800GT 512Mb (Single for beginning, then Dual in SLI later if needed)
HDD: 1x 36Gb WD Raptor 16Mb Cache for OS (With a dual-fan cooler)
4x 500Gb Seagate Barracuda 32Mb Cache in RAID 0+1 for file storage
Basic DVD+-RW Drive and Floppy Drive, Nothing fancy here.
Shove that all in a Sunbeam Transformer Case with Green LED Fans/Cold Cathode tubes.
Running Vista Ultimate 64-bit.
Add that to a 22" Widescreen Acer Monitor, Razer Copperhead Gaming Mouse, Ideazon Stealth Gaming Keyboard.
Final Cost (Using Newegg.coms prices) is around $2250.
It's about the best I cam combine into. Other sites that specialize in building gaming compuers (pugetsystems/avadirect) price this system at $3500-$4400.
And compared to what I'm using to write this topic (HP Pavilion a404x with all stock except for an old GeForce 5200 Gfx card), I think I'm gonna be quite satisfied.
True it's not the best you could get. But I can't spend $1000 on a CPU. or $1500 on Dual 8800 Ultras.
In the end, I'd classify this as a high-end gaming computer, but not extreme.
I had Windows Vista 64 bit on my PC but went back to XP because many of the games I love to play are not compatable. You gain two things DX10 and 4 gig memory support, thats it. Vista 64 was also much more annoying with all the security warnings everytime you do the simplest things. Very tedious. Also things are harder to find like control panel settings are not the same.
you can turn the warnings off. its very simple. if your building a top of the line machine its a crime not to use a 64bit OS. All of the latest games run fine on vista. at least for me. I would also go with a q6600 instead of an amd chip, and an evga gts512. better bang for your buck. If your looking to run 3 year old games get xp.
If your using raid because you think its faster, its not. maybe 3 secs faster load times but no benefit at all in games. If you do alot of videowork, which I think you might be if your getting 2TB of HDD space, I hear that raid can help and its probably a good choice. but if its just for gaming skip raid.
The raptor is a waste of money also. the 7200.11 is just about as fast.
the AMD setup sounds sweet, and it's a breath of fresh air around here as nobody's really building anything that's not Intel. Definitely wait a little for the B3 Phenoms, as I hear the 9700-9900s are coming soon.
I've heard driver issues with Vista64, but its a great way to go if you wanna utilize that much ram. Make sure it's Vista Ultimate, as I have Ultimate 32bit, and aside from some minor annoyances (the security prompting for each app, the strange drive formatting issue i encountered) It's been very good to me.
790FX chipset is sweet, fast and stable, so no input there, However, last i heard, the ONLY chipset that will do SLI is the nVidia ones, and Intel's Skulltrail Mobo. If you're planning on running multiple GPUs, you could get a Pair of HD3870s for less than $400, or spring for the HD3870X2 then Wait for the Quadfire Drivers and the R700 cards to come out.
Storage-wise, Unless you're running hardware RAID for your OS(bootdrive), there isn't really a necessity for 0+1. you could get a Pair of 1Tb WD RE2s, or the Samsung Spinpoint F1 drives running RAID1 and get very close to the same result, with more space in your case. Also, the 75 or 150GB Raptor drives are ALOT faster than the 36gb(SATAI vs SATAII) but something you probably didnt notice on that mobo... you can run SAS!!!! Grab some 15k Cheetah SAS drives if you want some speed!