PSU Wattage Calculator
Build out your full system — CPU, GPU, RAM, storage, fans, RGB and cooling — to get an itemized power estimate and a recommended power supply size.
How the recommendation works
The calculator sums typical power draw for every component: the rated TDP of your CPU and GPU (increased if you overclock), ~25 W for the motherboard, ~5 W per RAM stick and SSD, ~9 W per hard drive, ~3 W per fan, ~4 W per RGB device, ~6 W for an AIO pump and ~10 W for USB peripherals. It then adds headroom — proportionally more for smaller builds — and rounds up to the nearest standard PSU size (450 W, 550 W, 650 W, 750 W, 850 W, 1000 W…).
Why you need headroom
Modern GPUs produce short transient power spikes well above their rated TDP — high-end cards can briefly draw double their sustained power. A PSU also runs most efficiently and quietly at around 50–60% load, and extra capacity leaves room for future upgrades without replacing the unit.
Which PSU should you buy?
Stick to reputable brands and at least an 80 Plus Gold efficiency rating for a gaming build. If you have a PCIe 5.0 graphics card, prefer an ATX 3.0/3.1 PSU with a native 12V-2x6 (12VHPWR) connector rather than adapters.