I'm looking to build my first OC system.  I know what PSU/RAM I'm getting (Antec 500w Neopower and Mushkin ddr2800 2x1GB) But I need suggestions for the chip and mobo.

So far I've read a lot about the e21x0 series of chips and I'll be going with one of those, probably an e2160, but I can't decide on the mobo.  My budget is around ~250 give or take 10 bucks.

I've read a lot of mixed reviews on the gigabyte ds3l P35 board so I can't make my final decision on the mobo just yet.  Does anyone have any other mobo suggestions for under $120?

I dont plan on going SLI ever, so thats not an issue.  I do currently have an 8800GTS 320MB from my last system that I'll be using until it dies.

I also plan on getting an AC7 cooler for it.

Any advice before I take the plunge?

Oh, forgot to mention that my budget is only for the mobo/chip/ram/CPU cooler.  I already have all the other components.

In your case, using the AC7 cooler will cause more problems that it's worth, since it doesn't do the secondary "downdraft" cooling of the stock Intel (and similar) CPU coolers.  The Intel should be fine (and save you money!).
I'd consider the next step up in the Gigabyte series, the GA-P35-DS3R.  If not, then the DS3L should be fine.

I'll just say don't get an nForce 680i motherboard. I hear P35's are good for OC on Intel based chips though.

What kind of case do you have?
 
If you have a side case fan that blows on top of the NB, then you wouldn't have any potential heating issues with the AC7.
 
A better cooler than the AC7 for just a little more is the Xigmatek S936. http://www.newegg.com/Product/Prod [...] 6835233001
 
It's on sale now for 15bucks with mir. It outperforms the AC7 by far.