Gaming Rig with Minimal Video Editing

Approximate Purchase Date: end of August or early September

Budget Range: Below $2500

System Usage from Most to Least Important: Gaming, 1080p Movies, Video Editing, Photo editing

Are you buying a monitor: Yes

Do you need to buy OS: Yes

Preferred Website(s) for Parts: Local Dealers

Location: City, State/Region, Country - Manila, Philippines

Overclocking: Maybe

SLI or Crossfire: Yes

Your Monitor Resolution: 1920x1080

Additional Comments: Quiet but High Performace - Diablo 3, Batman Arkham Asylum and Arkham City, WOW

Individual Parts
1. CPU: Intel Core i7-3770K Ivy Bridge 3.5GHz (3.9GHz Turbo)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

2. CPU Cooler: CORSAIR H100 (CWCH100) Extreme Performance Liquid CPU Cooler (stock fans will be replaced by Scythe Gentle Typhoon AP15 x4)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

3. Motherboard: ASUS P8Z77-V DELUXE LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

4. RAM: CORSAIR Dominator Platinum 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model CMD16GX3M2A1600C9
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

5. Storage: Crucial M4 CT128M4SSD2 2.5" 128GB SATA III MLC Internal Solid State Drive (SSD)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

6. Video Card: EVGA 02G-P4-2678-KR GeForce GTX 670 FTW 2GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready SLI Support Video Card (X2)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

7. Sound Card: ASUS Xonar DX 7.1 Channels PCI Express x1 Interface Sound Card
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

8. Case: COOLER MASTER HAF X RC-942-KKN1 Black Steel/ Plastic ATX Full Tower Computer Case
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

9. PSU: CORSAIR Professional Series Gold AX850 (CMPSU-850AX) 850W ATX12V v2.31 / EPS12V v2.92 80 PLUS GOLD Certified Full Modular Active PFC Power Supply
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

10. Mouse: Logitech G9x Black Two modes scroll USB Wired Laser 5700 dpi Gaming Mouse
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

11. Keyboard: Logitech G510 Black 18 Function Keys USB Wired Gaming Keyboard
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Some Questions.
1. Do I really need Intel i7 3770k? or Intel i5 3750k is enough?
2. Is EVGA a good brand?
3. Do I really need a new soundcard? or an onboard sound card is enough?
4. Do I need to change stock fans on Cooler Master Haf X?
5. Is 850watts enough or do i need to increase it?
Additional Question 6. Which mobo is better? Asus P8z77-v-deluxe? Gigabyte Z77X UP5TH? Gigabyte Z77X UD5H? or Asrock Z77 Extreme 6?

Comments are really appreciated.