XFX Radeon HD 6970

[Xioteon]

About to put my second one in, should I have any porblems?
Heres my rig:

- Processor Intel® Core™ i7 930 Processor (4x 3.20GHz/8MB L3 Cache)
- Processor Cooling Liquid CPU Cooling System [SOCKET-1366] - Standard 120mm Fan
- Ram CORSAIR Vengeance 16GB (4 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model CMZ8GX3M2A1600C9B
-Motherboard [SLI] MSI X58 PRO-E
-Motherboard USB / SATA Interface Internal USB 3.0 PCI-E 2.0 x1 Expansion Card
- Power Supply Antec High Current Gamer Series HCG-750 750W ATX12V v2.3 / EPS12V v2.91 SLI Certified CrossFire Certified 80 PLUS BRONZE Certified Active PFC Power Supply
- Primary Hard Drive 1 TB HARD DRIVE -- 16M Cache, 7200 RPM, 3.0Gb/s - Single Drives
- Optical Drive 24X Dual Format/Double Layer DVD±R/±RW + CD-R/RW Drive - Black
- Sound Card 3D Premium Surround Sound Onboard
- Network Card Onboard LAN Network (Gb or 10/100)

Installing:
Two - Video Card XFX HD-697A-CNFC Radeon HD 6970 2GB 256-bit GDDR5 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Video Card with Eyefinity