I am using the 3800+ x2, looking for something fast out of the box, looking to spend $150, I don't really overclock much but would like the added benefit and I dont plan on or have an SLI card.
Pretty much any board will work within 2-3% of each other. It really depends on how much or how little you plan on OCing in the future.
A lot of OCing. DFI Ultra-D
Not a lot of OCing...pretty much anything else will work and will OC a little. You can spend a lot less than $150 if you're not going SLI. Even the $70 ASRock board OC's well for a lot of people and runs both AGP and PCIe.