Short answer: most gaming PCs need between 650W and 850W. An RTX 5090 needs 1000W or more. Find your graphics card below, add headroom if you have a power-hungry processor, then round up.
Quick reference: RTX 50 series
These are the power figures for Nvidia's current cards, as listed in PC Gamer's spec table. "Recommended size" is the whole-system power supply size for a typical build.
| Graphics card | Card power | Recommended size |
|---|---|---|
| RTX 5090 | 575W | 1000W |
| RTX 5080 | 360W | 850W |
| RTX 5070 Ti | 300W | 750W |
| RTX 5070 | 250W | 650W |
| RTX 5060 Ti | 600W (MSI) | |
| RTX 5060 | 550W (MSI) |
RTX 5090 to 5070 from PC Gamer's spec table. RTX 5060 Ti and 5060 from MSI's recommendations for standard gaming builds.
AMD cards
AMD figures vary more, because partner cards are often overclocked. MSI recommends 750W to 850W for an RX 9070 XT build. Some factory-overclocked models ask for more: Tom's Hardware reported that the RX 9070 XT Red Devil's box recommends 900W, while AMD's Frank Azor confirmed other models would need less. Always check the box or product page for your exact card.
For older AMD cards, Tom's Hardware lists the RX 7900 XTX at 355W board power with an 800W recommendation.
Older Nvidia cards
MSI publishes ranges for previous generations. The lower figure is for a mid-range processor, the higher one for a top processor with overclocking.
| Graphics card | MSI range |
|---|---|
| RTX 4090 | 850W to 1300W |
| RTX 4080 / 4080 Super | 750W to 1250W |
| RTX 4070 Ti / Ti Super | 750W to 1000W |
| RTX 4070 / 4070 Super | 650W to 850W |
| RTX 4060 Ti | 550W to 750W |
| RTX 4060 | 550W to 650W |
| RTX 3090 | 750W to 1000W |
| RTX 3080 / 3080 Ti | 750W to 1000W |
| RTX 3070 / 3070 Ti | 650W to 850W |
| RTX 3060 / 3060 Ti | 550W to 750W |
Then account for your processor
The processor is the second biggest power user. Gaming-focused chips are fairly modest, but top multi-core chips can draw a lot under heavy work. Tom's Hardware lists the Ryzen 9 9950X at up to 230W and the Core Ultra 9 285K at up to 250W under maximum boost.
The card recommendations above already include a typical processor. If you have a top chip like these, or you plan to overclock, add about 100W.
Why spikes matter more than averages
Modern graphics cards don't draw a steady amount. They spike for fractions of a second, well above their rating. In MSI's testing, a whole system with an RX 9070 XT averaged around 455W to 501W in games, but peaked at 864W to 1029W.
A weak or older power supply can see those spikes as a fault and shut down, which looks like a random crash while gaming. ATX 3.0 and 3.1 power supplies are designed to handle short spikes like these, which is why every unit on my list meets one of those standards.
Why a little bigger is better
- Efficiency. Power supplies are most efficient around half load. KitGuru's tests of the Corsair RM850x peaked at about 92% between 45% and 55% load.
- Noise. A unit running well within its limit runs cooler, so its fan spins slower, or stays off entirely on semi-passive models.
- Upgrades. A bit of spare capacity lets you fit a faster card later without replacing the power supply.
What you don't want is a unit so large that your PC idles at a tiny fraction of its rating. Efficiency drops at very light loads, and you pay more for capacity you won't use.
Worked examples
| Build | Card says | Adjust | Buy |
|---|---|---|---|
| Ryzen 5 + RTX 5060 | 550W | None needed | 650W gives comfortable headroom |
| Ryzen 7 9800X3D + RTX 5070 Ti | 750W | None needed | 750W |
| Core Ultra 9 285K + RTX 5090 | 1000W | Add 100W for the processor | 1200W |
Mistakes to avoid
- Adding up every part's maximum. Parts don't all peak at once, so a straight total overestimates. Start from the card recommendation instead.
- Trusting the label on a cheap unit. A low-quality 850W unit may not deliver 850W safely. Buy from a trusted list.
- Reusing old cables when you upgrade. If you replace the power supply, replace every modular cable too. See why.
- Forgetting the connector. Wattage is only half the check. See the ATX 3.1 guide for the 16-pin graphics card plug.
Three steps to your number
- Find your graphics card in the tables above.
- Add about 100W for a top processor or overclocking.
- Round up to the next common size: 650W, 750W, 850W, 1000W or 1200W.
Prefer to plug in your parts? Use the calculator on the homepage. For a card-by-card list with picks, see the best power supply for your graphics card.
My picks at each popular size
- 650W pick · Tier ASeasonic Core GX ATX 380 Plus Gold · Fully modular · ATX · 650/750/850WCompact and solid for RTX 5070 class builds.Check 650W price
- 750W pick · Tier ACorsair RMx (2024)80 Plus Gold · Fully modular · ATX · 750/850/1000WA quiet, proven all-rounder for RTX 5070 Ti class cards.Check 750W price
- 850W pick · Tier ACorsair RMx Shift80 Plus Gold · Fully modular · ATX · 750/850/1000WMy pick for RTX 5080 class builds, if your case suits the side sockets.Check 850W price
- 1000W pick · Tier ACorsair RMx (2024)80 Plus Gold · Fully modular · ATX · 750/850/1000WThe headroom an RTX 5090 needs.Check 1000W price
- 1200W pick · Tier ACorsair HXi (2025)80 Plus Platinum · Fully modular · ATX · 1200/1500WFor an RTX 5090 with a top processor.Check 1200W price
Questions
Is 750W enough for an RTX 5070 Ti?
Yes for a typical build: 750W is the recommended size. Go to 850W if you have a top processor or plan to overclock.
Is 850W enough for an RTX 5090?
No. The recommended size is 1000W, and I would go to 1200W with a top processor.
Is 650W enough for an RTX 5070?
Yes for a typical build. 650W is the recommended size.
Can a power supply be too big?
It won't harm anything. Efficiency drops a little at very light loads and you pay more, but a modest step up is a good idea.
Why does my PC shut down when gaming?
It can be the power supply failing to handle the graphics card's short power spikes. See the guide to the signs of a failing power supply.
Do I need to add up every component?
No. Start from the graphics card recommendation, which already includes a typical system, then add headroom for a top processor.
Sources
- PC Gamer: Nvidia GeForce RTX 5080 (RTX 50 series spec table)
- MSI: recommended PSU table for Nvidia 30/40/50 series
- MSI: best PSU for AMD RX 9070 XT
- Tom's Hardware: RX 9070 XT Red Devil packaging recommends 900W (February 2025)
- Tom's Hardware: Ryzen 9 9950X vs Core Ultra 9 285K
- KitGuru: Corsair RM850x ATX 3.1 review
As an Amazon Associate I earn from qualifying purchases. Prices and stock are on Amazon.