Question PSU Upgrade for RTX 3070


Dec 24, 2017
Hi im gonna do PSU upgrade for my newest RTX 3070 thank god im from lucky people that got one.Anyway gonna post my pc as of today (only teporary as i still cant get Ryzen 5600x).
And i have Corsair VS550 PSU for now but only temporary till ill get that new CPU as ive told.
Im looking for suggestions how many wattage PSU should i get and how to calculate that and if i can trust PSU calculating sites and/or if you know any good site you can suggest me that or just suggest me an PSU.

So my final Build should be like this:
CPU:Ryzen 5600x + CM Hyper 212 EVO (from old rig)
MB:Some B550 that i still need to consider
GPU: msi rtx 3070 ventus 2x
Memory: Corsair Vengeance RGB PRO 2x8 GB 3200Mhz
Case fans 120mm x5
HDD 1TB x2 or 1TB + 2TB will see doesnt matter ill have 2 HDD because i want to save my old files in old HDD
one SSD

I dont trust PSU calculating sites thats why i asking here if someone have good reputation with those or if someone can help me with this decisions i would be gratefull. BTW i dont need modular PSU im not looking for that fancyness i just want it trustworthy and working propperly. Thank you if you have any suggestions.
If i missed something just ask.
A Good 650 watt would be enough, if you want some more head room go for a 750 watt.

Stick to Tier A