What PSU do you need for the RTX 4080?
With a 120 W CPU such as the Ryzen 7 9800X3D: 750 W is the safe choice, and a good-quality 650 W unit also covers the card's measured draw.
With a 65 W CPU, 750 W (650 W good-quality). With a 253 W CPU, 850 W.
Measured card power, not rated power: 304 W average while gaming, 371 W highest 20 ms spike.
Is my power supply enough? 450–1600 W
Each cell is the sustained gaming load as a share of the label. ✓ Safe: the load fits, the card's measured spikes stay under the label, and the size meets the higher published recommendation (750 W). ✓ Good unit: the measured draw fits, but the size is below 750 W — fine with a well-reviewed unit, not with a no-name one. ✗: not recommended — the steady load is over 80% of the label, a spike passes the label, or the size is below 750 W without meeting the good-unit bar.
| PSU | 65 W CPU e.g. Ryzen 7 9700X | 120 W CPU e.g. Ryzen 7 9800X3D | 253 W CPU e.g. Core i7-13700K |
|---|---|---|---|
| 450 W | ✗ 99% | ✗ 111% | ✗ 140% |
| 550 W | ✗ 81% | ✗ 91% | ✗ 115% |
| 650 W | ✓ Good unit 68% | ✓ Good unit 77% | ✗ 97% |
| 750 W | ✓ Safe 59% | ✓ Safe 67% | ✗ 84% |
| 850 W | ✓ Safe 52% | ✓ Safe 59% | ✓ Safe 74% |
| 1000 W | ✓ Safe 44% | ✓ Safe 50% | ✓ Safe 63% |
| 1200 W | ✓ Safe 37% | ✓ Safe 42% | ✓ Safe 53% |
| 1600 W | ✓ Safe 28% | ✓ Safe 31% | ✓ Safe 40% |
Sustained load = card's measured gaming draw + CPU at its TDP (Intel 12th gen and later: maximum turbo power; games usually draw less, so this errs high) + 75 W for board, memory, drives and fans: 65 W CPU 444 W · 120 W CPU 499 W · 253 W CPU 632 W.
Measured power draw
| Gaming average | 304 W |
|---|---|
| Highest 20 ms spike | 371 W |
| Rated board power | 320 W (NVIDIA) |
| Card measured | NVIDIA GeForce RTX 4080 Founders Edition |
Measurements are from TechPowerUp's review of this card, which records card-only power with dedicated equipment. TechPowerUp's test method has changed over the years, and newer test runs of the same card can read higher — one more reason the safe choice never goes below the published recommendations.
Why PSU recommendations disagree
- NVIDIA: 750 W (spec page). The maker's figure has to cover any CPU and any power supply.
- TechPowerUp: 650 W minimum, sized from the card's measured draw.
- Most online calculators add up rated power (TDP) for every part and then add a margin. Rated power is not what a card or CPU actually draws in games, which is why their answers can differ by 100 W or more.
- This page: the safe choice never goes below 750 W, the higher of the published figures. The good-unit size uses the measured draw and never goes below TechPowerUp's minimum. See the methodology.
Connectors
Cards in this power class use the 12V-2x6 (12VHPWR) connector or three 8-pin PCIe connectors depending on the board partner. If yours has the 16-pin connector, a power supply with a native 12V-2x6 cable avoids adapters.
When to step up a size
Overclocking, a factory-overclocked card, more than four drives or a lot of fans and RGB each add tens of watts. If two or more apply, take the next size up. Check your exact card's spec sheet too — some board partners list a higher minimum.
Try your exact CPU in the PSU calculator · Best CPU for the RTX 4080