Just buy 7 AntMiner S3 units from Bitmaintech.com. 7 x 440 = 3080 GH or 3.08 TH

http://Bitmaintech.com

Please read the info in the S3 support thread here on this forum so you know what power supplies you will need.

https://bitcointalk.org/index.php?topic=671189.0;topicseen

Hope this helps.