PSU Wattage Calculator

Pick your CPU + GPU + drives. Get a recommendation with real headroom for OC spikes and ATX 3.1 transient loads.

CPU

GPU

NVMe / SSD Count

Spinning HDDs

Case + Rad Fans

RAM Sticks

Workload Profile

RGB-heavy build (fan hubs, LCD pump, strips)Plan for ATX 3.1 / 12V-2x6 transient (recommended for 4090 / 5080 / 5090)

Recommended PSU

650

watts

For AMD Ryzen 7 7800X3D + NVIDIA RTX 4070 Super

CPU120 W

GPU220 W

Motherboard60 W

RAM (2× 5W)10 W

NVMe (2× 8W)16 W

HDDs (0× 10W)0 W

Fans (6× 4W)24 W

Peripherals15 W

Base draw465 W

×1.25 headroom581 W

Shop matching PSUs →

Top picks at 650 W

Verified ATX 3.0 / 3.1 units that fit your spec. Click any card to buy on Amazon with our affiliate tag.

Corsair · 650W

RM650e (ATX 3.1)

Seasonic · 650W

FOCUS GX-650 (Gold)

Thermaltake · 650W

Toughpower GF3 650W

How this is calculated

We sum the TDP of every component, apply a category-tested headroom multiplier (1.25× stock, 1.35× OC, 1.5× sustained), and then add an ATX 3.1 transient buffer if you're running an RTX 4090, 5080, or 5090 — those cards momentarily pull 2× their rated TDP for milliseconds, which is exactly what kills marginal PSUs. The result is rounded up to the next standard PSU class (650 / 750 / 850 / 1000 / 1200 / 1600).