First Homebuilt...

http://www.tomshardware.com/forum/261222-31-build-advic...

I know you covered a lot of this in your first post. But filling this out (to let us know as much info as possible) will go far in helping you out.

CPU - Intel Core i3-2100($124.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

RAM - G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333($29.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Motherboard - ASUS P8H61-M LE/CSM (REV 3.0) ($69.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

HDD - Western Digital Caviar Blue WD5000AAKX 500GB($89.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

ODD - SAMSUNG 22X DVD Burner($15.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Video Card - SAPPHIRE 100315L Radeon HD 6850 1GB($134.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Chassis - Thermaltake V3 Black Edition($44.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

PSU - CORSAIR Builder Series CX430 V2 (CMPSU-430CXV2) 430W($44.99)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Subtotal - $555.92 ($510.92 after MIR)

This is a very balanced system, but not many room for upgrade. If you can up your budget a little more, you can get a better psu which is the Antec High Current Gamer Series HCG-620 620W

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

But, this is still a very balanced pc that can run about most current games at 1080p with mid to high settings. Skyrim and battlefield 3 can run high

Do you need an OS?

If you do, check the $500 build in my sig. That's G860 + HD6770.

If you already have an OS, check the $600 build in my sig. Core i3 2100 + HD6870.