Cost per hour of gaming at 26.32p per kWh (UK average), the live standard variable rate since 1 October 2026. Figures are each card's maximum rated power.
The short answer
Your graphics card is the biggest power user in a gaming PC. NVIDIA rates the RTX 50 series cards from 250 watts (RTX 5070) up to 575 watts (RTX 5090). These are maximum figures. In many games the card runs below its limit, especially with a frame rate cap.
RTX 50 series running costs
| Card | Rated power | Card per hour | Whole PC per hour (estimate) | Whole PC per year (3 hrs/day) |
|---|---|---|---|---|
| RTX 5090 | 575 W | 15p | 20p | £216.15 |
| RTX 5080 | 360 W | 9.5p | 14p | £149.87 |
| RTX 5070 Ti | 300 W | 7.9p | 12p | £129.69 |
| RTX 5070 | 250 W | 6.6p | 11p | £115.28 |
The whole-PC estimates add about 150 to 175 watts for the processor, motherboard, memory, fans and power supply losses. A high-end processor under heavy load can add more.
Is a more powerful card worth the running cost?
At 3 hours a day, the gap between an RTX 5070 PC and an RTX 5090 PC is roughly £100.87 a year. That's real money, but it's small next to the difference in purchase price. If you want to cut it, a few settings help a lot:
- Cap your frame rate to your monitor's refresh rate, or a little below it. The card stops working flat out to render frames you never see.
- Turn on DLSS. Rendering at a lower resolution and upscaling usually uses less power for the same frame rate.
- Undervolt or set a power limit. Cutting the power limit by 10 to 20% often costs only a few percent of performance.
What size power supply do I need?
NVIDIA recommends a 1,000 W supply for the RTX 5090, 850 W for the 5080, 750 W for the 5070 Ti and 650 W for the 5070. A bigger power supply doesn't make your PC use more electricity. It only supplies what the parts ask for.
Work out your own total with the calculator, or see the full gaming PC running costs.
Sources: Corsair (NVIDIA specs), Evetech, Octopus Energy tariff data.