A typical desktop computer tower uses about 60-150 watts during everyday work, roughly 100 W, not counting the monitor. Compact and Apple-silicon desktops can idle under 10 W; powerful workstations can exceed 250 W.
- Running watts
- 100 WTypical; 40–250 W across models
- Starting watts
- NoneNo motor surge
- Per day
- 0.5 kWh5 h of use
- Current
- 0.8 AAt 120 V while running
Figures checked against DOE, ENERGY STAR and manufacturer data on . Your model's label is the final word.
Watts by model and setting
Most desktop computer models draw between 40 and 250 W while running; a typical one draws about 100 W. 100 W x 5 h/day of active use; sleep draw (a few watts) adds little. Monitor not included.
- Processor and graphics card: a dedicated GPU is the biggest single factor
- Workload: idle and web browsing use a fraction of full-load power
- Power supply efficiency (80 PLUS rating)
- Sleep settings: ENERGY STAR computers use about 30-40% less energy, partly by sleeping when idle
- Monitor and peripherals are extra
Running a desktop computer on a generator or power station
- Generator: at least 100 running watts. A generator rated 1,000 W or more covers it with room to spare.
- Power station: continuous output of at least 100 W. Pure sine wave output is the safe choice for motors and electronics.
| Power station capacity | Estimated runtime |
|---|---|
| 500 Wh | 4.2 h |
| 1,000 Wh | 8.5 h |
| 2,000 Wh | 17 h |
| 3,000 Wh | 25.5 h |
Based on 100 W average draw and 85% usable capacity.
- Use a pure sine wave inverter, power station or UPS; many PC power supplies with active PFC can misbehave on modified sine wave
- Budget for the monitor and router too: a full desk setup is often 150-200 W
- A UPS gives time to save work and shut down cleanly when the power drops
- Run any generator outdoors, well away from doors, windows and vents; never in a garage or basement, because of carbon monoxide.
Add it to the generator calculator
Questions people ask
How much power does a computer use in sleep mode?
Usually just a few watts. DOE's table lists 30 W or less in sleep, and modern ENERGY STAR desktops typically go well below that.
Does a desktop use more power than a laptop?
Yes. A typical desktop uses roughly two to four times the power of a laptop doing the same work.
Sources
- U.S. DOE Energy Saver: Estimating appliance and home electronic energy use (typical wattage table)
- Virginia Cooperative Extension: Estimating appliance and home electronic energy use (reproduces DOE wattage table)
- ENERGY STAR: Computers
- Generac wattage reference guide (PDF)
- Champion Power Equipment generator wattage chart (PDF)
- Apple Support: Mac Studio power consumption and thermal output