Regarding ATI's Crossfire concept: nVidea does the same thing with pairing cards, but it's called SLi. Depending what motherboard you've got dictates whether you'll be able to pair one brand or the other. You can still use an ATI card in a mobo designed for SLi, but you won't be able to Crossfire link 2 cards.
That said, buying 2 video cards isn't like 2 memory chips; you don't get twice the video processing power. Most recommendations I've ever seen say you won't want Crossfire (or SLi) unless you've got 2 displays. If you think you'll ever go BIG, you might buy a mobo supporting the dual card setup. For average gaming/graphics, you'll be fine with a single 256 or 512mb video card.
Nvidia 8600 series is a good choice, but as long as the graphics card supports directx 10 then you should be good for a while. Another suggestion though, I'd get an intel processor if I were you, they are currently much better than what AMD offers. Creative is your only real option for sound cards and don't forget to get a power supply powerfull enough to support all of you components, a pc power and cooling PSU is a good choice.
The gaming industry has been pretty slow in utilizing dual processing in both CPUs and GPUs considering that gamers are the largest target audience outside of professional use for high-end computers. Real world advantages of SLI or Crossfire are not as high as one would expect, and in some instances barely better than one high-end card. Dual and quad core CPUs offer little to no direct advantage to gaming other than being able to multi task while gaming. In fact, if there is any advantage other than the multi tasking, it can only be attributed to smaller process scale (we're approaching 45nm), larger cache sizes, higher FSB frequencies and better instruction sets. The actual core frequencies have dipped in the newer Core2 duo and AMD Solutions. Whereas the P4s and PentDs were approaching 4GHz, the Core2 Duos started at 1.8, but are OVERALL competitive with the P4s and PentDs. BUT...for single string processes such as gaming, raw GHz muscle still matters. If you wanted to go on the cheap, you would get a 3.6 GHz P4 for around $50 dollars. Just don't try to render hi resolution 3D models with it.
This is my new build, so give me some suggestions or input. I think it is fairly sufficient for power, memory, and overall performance. I may have some parts that arts compatible though, so a heads up would be nice.
It appears to be specifically a gaming build, but I consider it to have many other uses. I may have placed a part that could easily be substituted for a sufficient offbrand piece, so tell me if that is the case please.
Motherboard - Asus M2N-E SLI NVIDIA Socket AM2 ATX Motherboard / Audio / PCI Express / SLI Ready / Gigabit LAN / S/PDIF / USB 2.0 & Firewire / Serial ATA / RAID (2.7lbs)
Processor - AMD Athlon 64 X2 5400+ 2.80GHz OEM Processor (0.35 lbs)
Video Card - XFX GeForce 8600 GT XXX / 256MB DDR3 / SLI Ready / PCI Express / DL Dual DVI / HDTV / Video Card (1.2 lbs)
Sound Card - Turtle Beach Montego 7.1 Dolby Digital Live Surround PCI Sound Card (0.15 lbs)
Cd/DVD ROM - Lite-on SOHC-5236K Retail DVD-ROM Combo Drive - 52x32x CD-R/RW, 16x DVD-ROM, White (2.1 lbs)
DVD Burner - Sony DRU170C Retail DVD Burner - 18x DVD±R Burn, 16x DVD±R Read, 8x DVD+RW, 6x DVD-RW, 8x DVD±R DL, 12x DVD-RAM, 48x32x CD-R/RW, Internal (2.25 lbs)
Memory/RAM - Corsair Dual Channel TWINX 2048MB PC6400 DDR2 800MHz Memory (2 x 1024MB) (0.4 lbs) (X2 = 4gig)
HardDrive - Htachi / Deskstar T7K500 / 500GB / 16MB / SATA-300 / OEM / Hard Drive (1 lbs) - possibly X2 = 1 Terabyte, depends
CPU FAN - Thermaltake / Big Typhoon VX / 4 in 1 / 6 Heatpipes / 120mm Fan / CPU Cooler (2.55 lbs)
Mid-Tower Case - Apevia Blue X-Cruiser Case ATX Mid-Tower Case with Clear Side, Front USB, Audio and Firewire Ports (16.9 lbs)
Power Supply - Apevia / 520-Watt / ATX / Triple 80mm LED Fan / Black Aluminum / Power Supply (5.1 lbs) - Is this enough power you think?
Monitor - Acer AL1916WAB 19" Widescreen LCD Monitor - 5ms, 700:1, WXGA+ 1440x900, VGA(D-sub), Black (13.75 lbs)
Keyboard - Logitech G15 Gaming Keyboard (4.45 lbs)
Mouse - Razer Copperhead 2000 DPI High Precision Laser Mouse (Tempest Blue) (0.8 lbs)
Headphones/Headset - Razer Barracuda HP-1 Gaming Headphones (2.05 lbs)
Speakers - Tritton Sound Bite Portable USB Speaker System (0.75 lbs)
Give me your input I think this might be it. This of course is the full deluxe package.
If you want a reason for this, a comparison was needed in my opinion.
I wouldn't recommend buying a soundcard just to push headphones. That motherboard's output will do just fine for headphones and most speakers. Plus if you are buying USB speakers (which by the way look like a terrible investment), what's the point in a soundcard? That motherboard has S/PDIF (Sony-Phillips Digital Interface Format), meaning you can get a pure digital output for a serious set of speakers or receiver. Newer onboard sound technologies have done away with previous buzzing and hissing that plagued older versions. It may slightly bite into system resources, but you would never notice it unless you were listening to a listening to a 5.1/7.1 DVD audio disc or a SACD while gaming.
Also, save your money on the gaming keyboard. Performance gains are a joke and extra programmable buttons are for cheaters. The industry want to put gamer in front of any item just to milk a few extra bucks out of people. Choose any game and meet me online--I'll whoop A** with a $10 dollar IBM 108.
Everything else on your list is pretty stock for a good gaming machine. Nice selection.
Bleh I hate AMD processors but jesus that computer is pretty beefed up o.O boy would I love to have this in my computer GeForce 8600 GT lol nice selection ;D
I'm on my grind in search to find whats on my mind, its one of a kind!
I have the Geforce 8600, and its a pretty sweet card, but I would give my first born for a GeForce 8800 Ultra.
And I agree with Know1, scrap the USB speakers and the gaming keyboard, waste of money.
Also, most, if not all speaker systems now a days are self powered, and your sound card doesn't need much output to get them to produce sound, since the Amp for the speakers is self contained and powered.