CPU: Core i7-4770k
Motherboard: Gigabyte GA-Z87-D3HP
Power Supply: Seasonic 620W
HDD: 1x 1 TB WD Black (will upgrade to RAID 10 with 4 drives)
RAM: 8GB (2 X 4GB) Corsair Vengeance 1600
GPU: Sapphire Vapor-X R9-280X
OS: Windows 7 Home Premium
Whenever I try to play a game in full screen 720p HD, the computer freezes and crashes. It also crashes as soon as I try to up the resolution to 1080p HD. How much RAM would I need to play/edit videos at 1080p?