The minimum PSU is about 600W but I would recommend a 700W for the extra headroom. However it is not recommended to use that PSU for overclocking or having a high end gaming rig like yours. As it is a Tier 4 class, I really advise you to read this before proceeding buying anything. http://www.tomshardware.com/answers/id-1804779/power-supply-unit-tier-list.html
and try to aim for Tier 1 if you can afford it but a Tier 2 will do too and should be within most gamer's budget.
The minimum PSU is about 600W but I would recommend a 700W for the extra headroom. However it is not recommended to use that PSU for overclocking or having a high end gaming rig like yours. As it is a Tier 4 class, I really advise you to read this before proceeding buying anything. http://www.tomshardware.com/answers/id-1804779/power-supply-unit-tier-list.html
and try to aim for Tier 1 if you can afford it but a Tier 2 will do too and should be within most gamer's budget.
No it is not according to a thread on Tom's PSU Tier. It is a Tier 4 but the except for some GX series which are in tier 2 and 3 but not this one you listed.
Why are you referring to a Corsair now. I would actually get it, but please provide the full specs and I will see which PSU suits best and do you have a budget? And keep in mind a good PSU is important or you may loose all your parts when the PSU breaks down or burn.
Let's say you plan to upgrade the CPU in the future or GPU or maybe even SLI so the 650W will not support it.So basically it's planning ahead and thinking about the future.
if i not upgrade for the future i dont have to buy 650w right
If you don't plan to upgrade in the future, then stay with the 650W. But if you plan to upgrade but you still want to buy the 650W, then you may need to upgrade the PSU. So basically I am planning ahead but who knows what the future holds.