What PSU do I need?
Power supply for the RTX 4090
Get at least a 1050 W power supply for the RTX 4090 (the maker recommends 850 W): our checker recommends 850 W with a Ryzen 7 9800X3D, 1050 W with a Core i7-14700K. The cheapest one in our catalog that fits is the be quiet! Pure Power 13 M 1200W Gold (ATX 3.1). It uses the 12V-2x6 plug, so an ATX 3.1 unit is the cleanest choice.
Key facts· updated
- The RTX 4090 draws about 450 W while gaming (maker spec pages, checked Oct 29, 2026).
- The maker recommends an 850 W power supply for the RTX 4090 (maker spec pages, checked Oct 29, 2026).
- A PC with the RTX 4090 and a Ryzen 7 9800X3D draws about 650 W while gaming, so PC Atlas recommends an 850 W power supply (the higher of the maker's advice and 1.3× the draw, rounded up to 50 W).
- A PC with the RTX 4090 and a Core i7-14700K draws about 783 W while gaming, so PC Atlas recommends a 1050 W power supply (the higher of the maker's advice and 1.3× the draw, rounded up to 50 W).
- Power plug on the RTX 4090: The 12V-2x6 plug (the updated 12VHPWR). An ATX 3.1 power supply has the cable built in; older ones use the adapter in the box.
| Card's gaming power | ~450 W |
|---|---|
| Maker's PSU advice | 850 W |
| With a Ryzen 7 9800X3D | ~650 W total while gaming → 850 W PSU |
| With a Core i7-14700K | ~783 W total while gaming → 1050 W PSU |
| Power plug | The 12V-2x6 plug (the updated 12VHPWR). An ATX 3.1 power supply has the cable built in; older ones use the adapter in the box. |
Card power, plug and the maker's advice from maker spec pages (checked 2026-10-29). Total = processor + card + ~80 W for the rest; recommended = the maker's number or 1.3× the total, whichever is higher, rounded up to 50 W (the same rule Build a PC checks).
Power supplies that fit (1050 W+)
| Power supply | Watts | Size | ATX 3.1 | Price today |
|---|---|---|---|---|
| be quiet! Pure Power 13 M 1200W Gold (ATX 3.1) | 1200 W | ATX | Yes | $163Sample |
| NZXT C1200 Gold 1200W (ATX 3.1) | 1200 W | ATX | Yes | $200Sample |
| Corsair RM1200x SHIFT 1200W Gold (ATX 3.1) | 1200 W | ATX | Yes | $255Sample |
| Corsair HX1200i 1200W Platinum (ATX 3.1) | 1200 W | ATX | Yes | $288Sample |
Cheapest first, ATX 3.1 units first; SFX units are for small cases. Prices last checked ; Sample = PC Atlas catalog estimate, not a live store price.
Questions
What wattage power supply do I need for the RTX 4090?
Get at least a 1050 W power supply for the RTX 4090 (the maker recommends 850 W): our checker recommends 850 W with a Ryzen 7 9800X3D, 1050 W with a Core i7-14700K. The cheapest one in our catalog that fits is the be quiet! Pure Power 13 M 1200W Gold (ATX 3.1). It uses the 12V-2x6 plug, so an ATX 3.1 unit is the cleanest choice.
What power plug does the RTX 4090 use?
The 12V-2x6 plug (the updated 12VHPWR). An ATX 3.1 power supply has the cable built in; older ones use the adapter in the box.
Do I need an ATX 3.1 power supply?
Not strictly: the RTX 4090 comes with an adapter for 8-pin cables. An ATX 3.1 unit has a native 12V-2x6 cable (one clean cable, no adapter) and is built to handle the short power spikes these cards make.
Is 850 W enough for the RTX 4090?
With a Ryzen 7 9800X3D-class processor, yes: the whole PC draws about 650 W while gaming, and 850 W leaves headroom for power spikes. With a Core i7-14700K (about 783 W total), step up to 1050 W.