Do PC Cases Come With a Power Supply?

Budget for a new PC build and the case usually feels like one of the smaller line items, until the question comes up: do PC cases come with a power supply, or is that another $80 to $150 to add to the cart? Most builders find out the hard way that this one is not a safe assumption either way.

The Short Answer

For the vast majority of cases sold for custom builds, no, a power supply is not included. The case and the PSU are treated as separate purchases in the DIY PC market, similar to how a motherboard and CPU are sold apart even though neither works without the other.

There are two clear exceptions:

• Combo/bundle cases: Some budget-oriented cases, often under $60, ship with a basic PSU already mounted inside. These are marketed toward office builds or first-time budget builders.
• Prebuilt desktops: A Dell, HP, or gaming-brand prebuilt PC always has a power supply installed since it arrives as a working computer, not a bare case.

Why PSUs Are Usually Sold Separately

Power supply needs vary wildly by build. A case designed for a basic office PC and a case aimed at a high-end gaming rig with a power-hungry graphics card have completely different wattage requirements, so bundling one fixed PSU would not work for most buyers.

• Wattage needs range from around 450W for light builds to 850W or more for high-end gaming rigs.
• Efficiency certification (80 Plus Bronze, Gold, Platinum) affects both price and long-term power costs.
• Modular versus non-modular cabling affects build cleanliness and airflow.

Letting buyers choose their own PSU means the power supply actually matches what is going inside the case.

Reality Check: A bundled PSU in a cheap case combo is rarely something to build a serious gaming PC around. These units are typically lower wattage, non-modular, and carry shorter warranties than standalone PSUs from established brands.

If a Case Does Include a PSU

A few things are worth checking before relying on a bundled power supply for an actual build:

• Rated wattage, and whether it covers the CPU and GPU planned for the build.
• 80 Plus certification level, if any is listed at all.
• Warranty length, since reputable standalone PSUs often carry 5 to 10 year warranties while bundled units may offer far less.
• Connector types, particularly whether it has the PCIe power connectors a modern graphics card needs.

For anything beyond a basic browsing and office PC, most builders end up buying a separate PSU from a known brand regardless of what came in the case box.

Budgeting for a Separate Power Supply

Since most cases will not include one, it helps to treat the PSU as its own line item from the start of a build budget. A well-reviewed 650W 80 Plus Bronze unit is often enough for a solid mid-range gaming build, while higher-end GPUs push that requirement up. Checking manufacturer PSU wattage calculators or a component list against a compatibility tool avoids under-buying power.

1. Are cases with a built-in power supply cheaper overall?

Sometimes, but the savings often reflect the lower quality of the bundled PSU rather than a genuine discount. Comparing the combo price against buying a quality case and a quality PSU separately usually shows the difference is smaller than expected.

2. Can I use my old PSU in a new case?

Usually yes, as long as it physically fits (ATX PSU form factor is standard in most cases) and has enough wattage and the right connectors for the new components. Just confirm the case supports standard ATX PSU mounting, which nearly all mid-tower and full-tower cases do.

3. Do small form factor cases include a PSU?

Rarely, though some SFX-based mini-ITX cases are sold as kits with a matched small form factor power supply due to the tight internal clearances involved. It is still worth confirming on the specific listing.

4. How do I know what wattage PSU I need if the case doesn’t include one?

Add up the estimated power draw of the CPU and GPU, then leave headroom of roughly 100 to 150 watts for other components and future upgrades. Most PSU manufacturers offer free wattage calculator tools based on the exact parts list.

The Bottom Line

Assume a power supply is not included unless the case listing explicitly says so, and treat any bundled PSU with a healthy amount of scrutiny before trusting it with an expensive graphics card.

This article reflects general PC building guidance based on publicly available manufacturer information at the time of writing; always confirm PSU inclusion and specs on the exact case listing before purchasing.