1st Time Considering AMD/ATI machine, But Clueless

Okay, this is my 1st time ever considering an AMD build for my little brother and some testing and research on it 1st (To understand more about AMD machines)

Okay, I pick this for AMD build
AMD AthlonX2 7850+ - 63USD+/-
Motherboard - No idea..at all

And this Intel Build
Intel E5300 - 70USD+/-
Asus P5KPL-AM - 50USD+/-

Paired with
2X2GB Kingston DDR2-800 - 48USD+/-
ATI 4850/512 - 100USD+/-
Corsair CX400

1st question is... which mobo should I take for the AMD build.
2nd question, can 7850+ overclock to 3.0GHz+ like the E5300? On stock Cooling
3rd question, consider the pricing which is quite close between them, which should I go for ?

Thanks in advance

Wops..
Budget is under 300USD
Monitor is not needed
Mouse Keyboard not needed
Casing, HDD and PSU is not concerned in the calculation, I can take one anytime lol..

Theres an article over at anandtech comparing the e5300 and the 7850 . At stock speeds in games the 7850 had a clear lead , but was behind in most productivity apps [ I seem to recall ]

AMD has moved on a bit since then and rather than the 7850 how about

AMD Athlon II X2 250 Regor 3.0GHz + ASUS M4A78-E AM2+/AM3 AMD 790GX HDMI ATX AMD Motherboard
combo $169 after MIR
http://www.newegg.com/Product/Comb [...] mbo.211697

That cpu is a newer generation and stronger than the Kuma , the price is sensational , and you can upgrade by adding any am2 or am3 processor later on

Read this article : http://www.tomshardware.com/review [...] 324-9.html

This RAM
OCZ SLI-Ready Edition 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800
http://www.newegg.com/Product/Prod [...] 6820227269
is $36 after MIR

Shoooooooot...now only I noticed that I have 2X1GB Corsair XMS2-800 hiding in my tool bag...
So Ram is not in concern as well
Thanks

what country are you in , and what website are you going to buy from?

Im in New Zealand and sometimes my local pricing is a lot different to the US .Its hard to make recommendations without knowing prices....