PSU help for i3-4170, Gtx-960 (and possible future upgrade)

[elodman]

Greetz!

Great sorry for perhaps not having done sufficient search, although in the recent days I have done nothing else - because of my B. Friday and Cyber Monday purchase. Now, I have a deadline to test if everything is / will be OK within a few days after having shopped the yet-to-be-obtained / assembled parts. (sorry for my might be wrong English).
So I read extremely many reviews and guides on mobos, cpus, gpus, cases, and hope, I have chosen well.

Now come the last 2 components: PSU (and RAM).

I am really intimidated by PSU guides, e.g.:
http://www.hardwaresecrets.com/everything-you-need-to-know-about-power-supplies/
http://www.tomshardware.co.uk/forum/324368-28-computer-power-supplies-guide/page-2
http://www.overclock.net/t/525110/basic-power-supply-buyers-guide

I found the PSU tier list, too:
http://www.tomshardware.co.uk/forum/id-2547993/psu-tier-list.html

But there are so many factors, I am in need of some help for my config:

• 
  i3-4170,
  Asus NVIDIA GEFORCE GTX 960 OC STRIX, 2048MB, GDDR5, 128bit,
  Asus Z97-C,
  8 GB DDR3 RAM,
  case: Inwin mana 136 ATX,
  6 fans, 1 hdd, 1 ssd, 1 odd
  NO Overclock or any weird thing planned.

The below calculations are from http://outervision.com/power-supply-calculator :
"Load Wattage: 302 W "
"Recommended UPS rating: 600 VA "
"Recommended PSU Wattage: 352 W "
"Amperage (combined)
"+3.3V"" +5V +12V"
"8.0 A 11.6 A 18.1 A"


But, strangely, on http://www.logicalincrements.com/#!/ my config qualifies for the Great category, where a 620 Watt PSU is recommended !!!
(SeaSonic S12II 620 Bronze 620W ATX12V V2.3 / EPS 12V V2.91 80 PLUS BRONZE Certified Active PFC Power Supply )

Now I am completely at a loss to see such huge differences between advised Watt performance, not even trying to consider Volt and Amp, pins, size!!! Also, possibly some protection against fatal disasters (over current) would be fine.

((( In addition, in a few years I would upgrade to i5, and a stronger GTX.
For which the calculations:
"Load Wattage: 384 W "
"Recommended UPS rating: 750 VA "
"Recommended PSU Wattage: 434 W "
"Amperage (combined)
"+3.3V"" +5V +12V"
"8.0 A 11.6 A 24.9 A ))))"


But perhaps then the whole config or PSU should be replaced.

Plz. recommend me a few Tier 2 category PSU-s or hints to go further in research! Should I bother with many details, or a simple recommended PSU "knows all the tricks & rulez them all"?

I thought of a quite affordable Antec High Current Gamer HCG-520 520W, as the fine tier 2 Seasonic and XFX are much more expensive in our country.

Thanx for perhaps having read all and maybe answering.

 

[defaultluser]

Worst case your system will use 200w while gaming. 520w is a bit overkill, but gives you room in the future for an overclocked i7 plus GTX 980 ti.

 

[4745454b]

I thought the same thing as defaultluser. Draw while gaming should be ~200, perhaps a bit more. Why would anyone say you need a 600W+ unit for that? Crazy. I'm running a 3770K and 7950boost/280 on a 450W unit. A QUALITY 450W unit will run your system just fine. I wouldn't go higher then a QUALITY 550W unit.