Originally Posted by isaacmajdi
so if I kept my system as it is (without overclocking + without adding any cards) the 650VA version will be enough? and if I upgraded my PC heavily should I get the 800AV or 1000AV version?
Without any overclocking, even 600VA would be enough even if you're in the middle of a video game.
With CPU overclocking (like say to 4.7 GHz), a 650-750VA UPS is enough.
What kind of heavy upgrades are you talking about? Like two GTX Titans? I mean, with two GTX Titans and a CPU overclock like I mentioned above, you're right that you'd need about 1000VA, perhaps as much as 1100. So, it all depends on what kind of upgrades you're talking about.
Anyway, I still don't know which UPS units are good and which ones are bad.