PSU Wattage Calculator

Find out how many watts your PC needs. Pick your parts below for an instant, accurate power supply recommendation.

PSU Wattage Calculator – How Many Watts Does Your PC Need?

🔲 Component

Processor (CPU)

🖥️ Component

Graphics Card (GPU)

RAM sticks

SSD / NVMe drives

Hard drives (HDD)

Case & CPU fans

Liquid cooling (AIO)

RGB lighting

Overclocking

Select a CPU and GPU, then click Calculate Wattage.

Recommended power supply size

80 PLUS Bronze or higher

POWER BREAKDOWN

How Many Watts Does Your PC Need?

Your PSU wattage depends mostly on your CPU and GPU, since those two parts draw the majority of the power. RAM, storage, fans, and cooling add smaller amounts on top. Pick your parts above for an exact figure, or use the guide below as a quick reference.

What Affects PSU Wattage

GPU power draw the single biggest factor in most builds.
CPU power draw more cores and higher clock speeds mean more watts.
Overclocking pushes both components to draw noticeably more power.
RAM, storage, and fans small on their own, but they add up.
Future upgrades a bit of extra wattage now avoids buying a new PSU later.

PSU Wattage Guide by Build Type

Build type	Typical PSU wattage
Budget / office PC	450W – 550W
Mainstream gaming PC	650W – 750W
High-end gaming PC	850W – 1000W
Enthusiast / overclocked build	1000W – 1200W
Extreme / flagship build	1200W+

How This Calculator Works

It adds the rated power draw of your chosen CPU and GPU to the load from your RAM, storage, fans, and cooling. Then it adds roughly 30% headroom on top covering power spikes, PSU efficiency loss, and future upgrades and rounds up to the nearest standard PSU size.

PSU Calculator FAQ

It depends entirely on your parts mainly your GPU and CPU. Most complete gaming PCs fall somewhere between 550W and 850W. The fastest way to get your real number is to select your parts in the calculator above.

Most gaming builds need 550W–850W depending on the graphics card. As a general rule, a quality 650–750W unit covers the majority of mid-range to upper mid-range builds comfortably.

For many mid-range builds, yes a card like an RTX 4060 or RX 7600 runs comfortably on 500W. Step up to 650–750W for cards like the RTX 4070 or 4070 Ti, and 1000W+ for flagship cards like the RTX 4090 or 5090.

A regular desktop draws around 30–70W at idle and 100–250W under load, depending on its parts. Gaming PCs sit higher usually 50–100W idle and 300–600W while gaming, with high-end builds pushing past 500W.

Systems built around an RTX 4080 or 4090 typically draw 500–700W under load, and RTX 5090 builds can spike even higher for brief moments. These are best paired with an 850W–1200W power supply.

Bronze is the practical minimum. For 650W and above, Gold is the sweet spot for efficiency and reliability. For 850W+ builds, Gold or Platinum is worth the extra cost, especially if the PC runs for long sessions.

Yes overclocking increases power draw on both CPU and GPU. That’s exactly what the Overclocking toggle in the calculator accounts for, adding the extra headroom automatically.

Typically random restarts or shutdowns under load especially mid-game when the GPU ramps up. In severe cases, the PC won’t boot at all. If these symptoms started after a GPU upgrade, the PSU is the likely cause.

No. A PSU only draws the power your components actually request a 1000W unit powering a 400W system just runs cooler and quieter, with room to grow. The only real downside is the extra cost upfront.

No. A power supply only pulls what your components ask for, so a 1000W unit running a 400W system draws about the same as a 500W unit would in that system. More wattage capacity just means more headroom, not more consumption.

Modern GPUs can briefly spike well above their rated draw. PSUs also lose a little capacity as they age and run most efficiently below their max load. The headroom accounts for all of that.

Very littl a single 120mm fan typically draws under 2W, and even a full set of case fans plus a CPU cooler adds only around 10–20W to your total build.

Roughly 20–60W depending on size and brightness a 24-inch 1080p screen sits near 20–30W, while a large high-refresh or 4K display can reach 60W or more. Monitors run off their own outlet, so this isn’t included in your PSU sizing.

Very little usually 3–6W, just enough to keep memory active for a quick wake-up. Fully powered off, it draws close to zero aside from a trace amount for the power button and wake-on-network features.

A decent PSU usually lasts 5–10 years, and a quality unit can outlast several other components. Cheaper units or ones running consistently near their limit tend to wear out faster.

Match it to your system’s real draw plus your monitor, then add margin for runtime. A gaming PC pulling 400–500W pairs well with a UPS rated around 800–1000VA, giving a few minutes to save work and shut down safely during an outage.

Most desktop cases use the standard ATX form factor, so a regular ATX PSU fits the majority of builds. Small form factor cases usually need a compact SFX or SFX-L unit instead check your case specs before buying.