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PC build calculators: PSU wattage, bottleneck & GPU fitSpecs in.Clarity out.

Power budgets. Tight clearances. Part compatibility. Work through the numbers before the build.

Size my power supply Find my build
REFERENCE INPUTS. VISIBLE ASSUMPTIONS.Every estimate has limits. See the inputs, follow the sources, and check your exact parts.

01 / POWER WORKBENCH

Interactive estimate

Suggested PSU class

650W

465W estimated component load

72%Est. load
GPU 250WCPU 140WOther 75W

25% sizing buffer · 650W profile floor. CPU and supporting-component inputs are allowances, not measurements.

Manufacturer GPU specifications · Read RTX 5070 guidance

Check the exact card, CPU limits and cables before buying.

Open the full PSU calculator
10free tools for your next build
01–05PC budgets to start from
[→]sources and methods explained

The workbench

Check before you commit.

Explore all tools ↗
02 / TOOL

GPU clearance

Small case. Big card. Check the dimensions and find what still needs verifying.

03 / TOOL

Build compatibility

Work through sockets, memory, cooling, clearance and power for supported parts.

04 / TOOL

Local AI memory

Estimate model memory, context and overhead before choosing a graphics card.

Also on the bench:CPU + GPU balanceBuild costRAM latencyFPS & frametimeMouse sensitivity

Auto PC Builder · 2026 Meta

Your budget. A balanced starting point.

Five maintained tiers, selected for checked socket compatibility and sensible CPU/GPU balance. Tap a tier to see the full parts list, then verify exact components and current prices.

· Methodology

$500 build ↗$800 build ↗$1,200 build ↗$1,500 build ↗$2,000+ build ↗

Understand the numbers

Build knowledge, too.

All guides ↗
Field notes / Power

How much PSU headroom
do you actually need?

Follow the arithmetic from component draw to capacity, and understand what the estimate cannot tell you.

Read the worked examples ↗
Upgrade checks / 01Can you keep the cables when replacing a PSU? ↗Small form factor / 02Direct slot works. Riser gives a black screen. What next? ↗Build compatibility / 03Why is the GPU at x8 after adding an SSD? ↗

How to use the Auto PC Builder

Start with the amount you can spend on the tower, then treat the result as a complete starting configuration. Each tier reserves more of the budget for the graphics card as resolution increases, while keeping the platform, memory and power supply proportionate.

PC budget allocation diagram showing how GPU, CPU, platform, memory, storage, case and power supply share a build budget
A balanced budget is not an equal split. Gaming performance usually benefits most when the GPU receives the largest share without starving the supporting parts.

Step by step

  1. Choose the nearest budget tier; use the lower tier if tax, shipping and a Windows licence must fit inside the same limit.
  2. Read the performance target before the parts list. A 1080p esports build and a 4K visual-quality build prioritise different components.
  3. Open the full build page and verify motherboard socket, memory generation, case dimensions and PSU connectors.
  4. Compare live prices only after the configuration fits your monitor, games and upgrade plan.

How to read the result

The output is a pre-balanced editorial starting point, not a guarantee of a fixed frame rate. The performance target describes the intended class of use; individual games, settings, patches and cooling can move results up or down.

Common mistakes to avoid

  • Spending the entire budget on CPU and GPU while forgetting the case, cooler, fans, licence, tax and shipping.
  • Buying a high-end GPU for a low-refresh 1080p display when a monitor upgrade would improve the experience more.
  • Treating a chipset name as proof of compatibility without checking the exact board revision and BIOS.
  • Using a total wattage number without verifying connector type, cable count and physical PSU format.

Verify before you buy or change settings

Before buying, open the exact manufacturer pages for the CPU, motherboard, memory, case, cooler, graphics card and PSU. Confirm socket and BIOS support, RAM generation, cooler height, GPU length and thickness, PSU format and native power connectors. Prices and marketplace listings can change without notice.

Calculator logic and this guide were reviewed September 12, 2026. See the methodology and limitations.