How much electricity does a Ryzen 9 use when mining Monero?
A Ryzen 9 desktop mining Monero can draw roughly 120–250 watts at the wall with a CPU-focused setup, though heavily tuned systems may use less and unrestricted high-end builds may use more. Running nonstop, that range works out to 2.88–6 kilowatt-hours (kWh) per day—but your exact Ryzen 9 model, settings, and electricity rate determine your bill.
Why there isn’t one Ryzen 9 power figure
“Ryzen 9” covers several generations and models. A 3900X, 5950X, 7950X, and 9950X do not all use the same power or deliver the same mining speed. Laptop Ryzen 9 chips have different limits again.
Monero uses RandomX, a mining algorithm—the set of calculations your computer performs—that favors processors, or CPUs. Your electricity use depends on more than the processor’s name:
- Power limits: Factory boost settings can let the processor consume substantially more power.
- Mining threads: These are parallel workers running calculations. More workers do not always mean better efficiency.
- Cooling: Temperature affects how fast your processor can keep running.
- Other components: Memory, the motherboard, fans, graphics card, and power supply all contribute to the bill.
Treat the 120–250 W range as a planning estimate for a desktop, not a guaranteed reading for your machine.
Measure wall power, not just the CPU number
Your processor’s advertised TDP, or thermal design power, is a cooling specification—not a measurement of your whole computer’s electricity use. Software readings labeled “CPU package power” also leave out other components and power-supply losses.
For a useful answer, connect your computer through a plug-in electricity meter rated for your local outlet. Then:
- Measure the computer while it is idle.
- Start your actual Monero mining workload.
- Wait until temperatures and power readings settle.
- Record the average, or measure total kWh over several hours.
For browser mining, test the actual browser session you plan to use. Browser restrictions and implementation choices can change both power use and mining speed. Do not assume results from a dedicated mining program apply to your browser.
Turn watts into your electricity cost
A kilowatt-hour is the energy used by a 1,000-watt device running for one hour.
Use this formula:
Daily electricity cost = watts ÷ 1,000 × hours mining × your price per kWh
For example, if your Ryzen 9 computer draws 180 W and you pay $0.20 per kWh:
- 24 hours: 4.32 kWh, costing about $0.86.
- 30 days nonstop: 129.6 kWh, costing about $25.92.
- 8 hours a day: 1.44 kWh daily, costing about $0.29 per day.
These are electricity examples, not earnings estimates. Use your bill’s applicable per-kWh rate, including usage-based charges.
Count the power that mining actually adds
If you turn the computer on only to mine, count its full wall-power draw. If it would already be running, you can estimate the added electricity by subtracting its normal baseline use.
For example, 180 W mining minus 60 W idle equals 120 W added. Use comparable conditions, including the same monitor and background apps.
Reducing the CPU power limit can improve mining efficiency, but check both wall power and mining speed. For profitability, enter your measured figures into a live Monero calculator; browser fees and payout rules also matter.
The bottom line
Budget roughly 2.88–6 kWh daily for a Ryzen 9 desktop mining continuously, then replace that estimate with a wall-meter measurement. Your actual watts—not the Ryzen 9 label—tell you what mining costs.
