If I am using a MSI ZH77A-G43 LGA 1155 Intel H77 motherboard, want 16 Gb of RAM, and a 7770 GPU... would I be better to go for a Sapphire 7770 GPU and G.Skill Sniper RAM, or would I get an advantage with an all MSI system... MSI 7770 GPU, and MSI Z77 MPOWER RAM?
More aboutadvantage brand system
No, it does not make a difference.
I've heard that your computer can run smoother if they are all the same brand, is there no truth to that claim?
No. That is outrageous. It doesn't seem realistic for a system to have a boost based on branding.
No truth at all.
Only possible advantage is software offered by certain manufacturers such as Corsair Link, but honestly that's nothing much to worry about. Just purchase the most reliable parts you can find and you'll be all set.