Well, an AMD system board with two PCIx16 slots can be had for 100$, the processor will cost you another 150$-400$, memory will be about 150$ if you go for 2GB, I didn't see any GeForce 7900, but the 7800s will cost you 450$ each. So, taking the lower end prices, you're already at 1300$ without power, case, monitors, hard disks, optical drives, cooling, input devices, sound card, speakers, operating system, etc. Since you got dual video cards, you're going to want dual monitors, so that will be 400$-600$ for LCD, and 200$-400$ for CRT. That bumps the total up to 1700$. Getting a nice sound card and speaker system will run you around 200$, so total is 1900$. The Alienware/Dell and Gateway systems would probably cheap out on HDDs, you're going to want a smaller but really fast drive for OS and swapfile, and a larger drive for programs, data storage, etc. So that will be around 300$, and we're up to 2200$. Case, 100$; Power supply, 100$ for a nice one: 2400$. Optical drives are pretty cheap now, can probably get two for 50$. Gaming keyboard and mouse combos vary, upper-range would be about 75$. Total 2525$. Fans and memory coolers, we'll say about 25$. Windows XP x64 Professional is probably around 200$ retail. So, final price, nice round number of 2750$. Plus tax. Plus shipping. Plus the time to actually assemble everything, install everything, etc...
