PSU Wattage

[PastryRace]

What is the best way to find out how much wattage PSU you will need?

[LukeSavenije]

using stupidly expensive measurement tech on the pcie slots, eps power and all the other connectors to measure how much power there's exactly going through them

 

a more realistic answer: reviews of individual parts and adding around 50w to it works in most cases, just watch out that some measure in system power, while other in the target part

[Guest]

CPU TDP + GPU TDP and 50% headroom on top of that. This usually results to 450-550W in most mainstream systems nowadays which is all you need.