Buy the Azza PSAZ-1000A14 PSU from TigerDirect. I'm using it to power dual 6990s, overclocked. Runs like a dream, and I'm ordering 3 more. $99 with coupon LKH29905
they have the Sapphire 5850s still in stock. You'll want those or the ASUS ones because of the cooler design: best airflow.
Get the MSI board I mentioned, it works very well.
Buy an AMD quad athlon for $99 or something. Newegg has them.
Get your free ram, find a spare hard drive, and off you go. Should total you under $1000 I think, before shipping.
If you're worried about heat, buy these:
http://www.amazon.com/PCI-Express-Riser-Flexible-Cable/dp/B004XD74MC/ref=sr_1_1?ie=UTF8&s=electronics&qid=1305302419&sr=8-1While 1X risers will work perfectly, these are the only [cheap] ones I've found that will get to you in under 2 weeks
