Good rig you got there i dont see any problems with compatibility a single core processor could be just as good as a dual though and even better for gaming....The power supply could be a little too much a 500-550watt should do just fine, but if your planning to add another 7800gt or other harddrives and such 600watts would be good. Overall that would be an excellent rig good choice in parts. And I see that youve done alotta reaserch thats also good.
Looks really good. I'd keep that power supply as it'll keep you safe when you jump to SLI. A good power supply will cost more than a lesser brand, but it's worth the price. I can think of some slightly smaller power supplies that would do the job, but you're not going to really cut that much out of your budget (less than $10). If you want to cut something out of your budget, see what high performance RAM from GeiL or Patriot (specifically the LLK or +XBL stuff) you can snag 2 gigs for. The other thing that you could save some cash on is by opting for the 3800+ X2 or just going with a single-core altoghether. Since you mentioned overclocking, you might want to look at the Thermalright XP-90C or XP120 coolers.
You can get a AMD Athlon 64 4400 X2 from tigerdirect.com for 529.99 and a 19' lcd dvi monitor for alot less at the same place
Personally, I wouldn't buy or recommend using Tiger Direct. They don't have particularly inspiring customer service, their prices aren't anything spectacular, and I've seen a chunk of problematic parts come from them. Newegg, ZipZoomFly---those are my personal choices as I've spent around $1k, if not more, at each store.
I have gotten some really good parts off tigerdirect.com 1,8ghz pentium 4 (88 dollars about 2,5 years ago) 256mb ddr400 ram (10 dollars about a year ago) That p4 is not a bad one either as it is overclocked 50% with no effort on my part. I'll add now: their rebates are stupid, and I don't think they care about the customer.
Check that Maxtor have sorted there compatability issues out with nForce4 chip sets.Apparently there are/were majot problems.
