what do you think about this psu?

[Beyond]

http://www.newegg.com/Product/Product.asp?Item=N82E16817148001

to power:

3800+ x2
2gb corsair xms
dfi ultra-d
7800gtx
raptor later down the road

can you suggest anything much cheaper than this?

 

[shupola]

looks pretty good to me.

+12v@34A should be fine for that.