I need a new computer

Sure,

Get this
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2580524&CatId=333
ASUS Ivy Bridge Unlocked Barebones Kit - ASUS P8Z77-V LX Board, Intel Core i7-3770K CPU, Corsair 8GB DDR3 RAM Kit, Seagate 1TB HDD, 24x DVDRW, Thermaltake Commander MS-I Tower Case, Ultra 650-Watt PSU
$679.99

Get more Corsair DDR3 Ram to get a total of 16GB of RAM
http://www.newegg.com/Product/Product.aspx?Item=N82E16820145315
$48.99

Get the EVGA 02G-P4-2678-KR GeForce GTX 670 FTW 2GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready SLI Support Video Card
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130787
$419.99

To bring your total of $1147.96

If you want to save more money get this but don't mine a AMD Radeon HD card then here it is
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2628602&CatId=332
MSI 970A-G46 AMD 9 Series AM3+ Motherboard and AMD FX-8120 3.10 GHz Eight Core AM3+ Unlocked CPU and Sony Optiarc AD7280S-OB 24x DVDRW Drive and Corsair CMX4GX3M1A1333C9 XMS3 4GB DDR3 RAM and Bundle
$520.99

Get more ram $48.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16820145315

Get another AMD Radeon HD 7770 GHz Graphics and do CrossfireX with the other graphics card
http://www.newegg.com/Product/Product.aspx?Item=N82E16814102967
$134.99

A total of $704.97