Current rig is mining(single 6990) 720 mh/s but..waiting delivery of:

 XFX Radeon HD5850 Black Edition
 Radeon HD5850 1GB Powercolor graphics card
 ASUS EAH 5850 TOP 1GB Graphics Card 110% speed
Sapphire Radeon AMD HD 6850 1GB Graphics Card
AmazeTech ATI Radeon HD6850
VTX Radeon HD 6950 2GB GDDR5
 ASUS HD 6950 2GB GDDR5 DIRECT CU II AMD ATI RADEON
ASUS Radeon HD7850 HD 7850 DC II 2GB 2 GB GDDR5

GIGABYTE GV-R777OC-1GD Radeon HD 7770 GHz Edition"

Once machines are built should be pretty close to 3Gh/s without further overclocking