shreeux
Movie Buff
If you are currently running 6670 then most likely you are not a hardcore gamer in which case no matter what upgrade you do,you will never require a 750W psu(assuming you don't plan on spending 40-50k on a graphics card simply because you can).
Already I said, I go for future proof for PSU, That's why I choose maximum warranty.
Anyway, in between 10 years, I will upgrade at least 2 times change my GPU.
My System usage will be 15hrs/day, Due to My existing PSU makes a problem and repaired locally.
Not hardcore gamer...Due to this issues time being stopped playing.