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The short version
Real capacity, modern connectors and full modularity at a genuinely budget price.
See at Amazon — MSI MAG A850GL (opens in a new tab)The quiet option at the budget end, from a company whose whole reputation is noise.
See at Amazon — be quiet! Pure Power 12 M (opens in a new tab)The unit to stretch for if the budget can be persuaded to move at all.
See at Amazon — Corsair RM750e (opens in a new tab)The power supply is the component where cutting costs has the worst consequences, which makes the budget end of the market worth navigating carefully rather than avoiding entirely. There are good cheap units. There are also units whose stated capacity is a work of fiction. If the budget stretches further, our full power supply roundup picks up where this one leaves off.
What separates a cheap unit from a bad one
A warranty you can actually claim. Length is a proxy for what the manufacturer expects to happen, and a company offering a long warranty on a cheap unit is making a statement about its own failure rate.
Protection circuitry. Over-current, over-voltage and short-circuit protection are what stand between a fault and the rest of your machine. The units to avoid are the ones that do not mention them.
A manufacturer with something to lose. Established brands sell cheap units that are honestly specified because being caught doing otherwise costs them more than the margin.
Where the savings are real
Modularity, cable quality, acoustic engineering and warranty length are what you give up at this end. All four are genuine losses and none of them is a safety issue. That is the trade worth making. The MSI MAG A850GL (at Amazon, opens in a new tab) keeps full modularity and a modern connector at a genuinely low price, the be quiet! Pure Power 12 M (at Amazon, opens in a new tab) gives up some of that capacity for a noticeably quieter fan curve, and the Corsair RM750e (at Amazon, opens in a new tab) is worth the stretch if the budget can move at all.
Capacity, protection circuitry and honest specification are not places to save. Our power supply buying guide covers those fundamentals in more depth, and how much wattage you actually need walks through the sizing calculation referenced above.
How we chose
No load testing was done for this guide and none is implied. The reasoning rests on warranty terms, manufacturer track record, connector provision and honest capacity specification. Use the compatibility checker to confirm that a particular unit suits your parts before you commit.
Free tool PC Build Compatibility Checker — Will your GPU, PSU, cooler and case actually fit together?The picks
(opens Amazon in a new tab) - Band
- $ Budget tier
MSI MAG A850GL
Real capacity, modern connectors and full modularity at a genuinely budget price.
- Native modern graphics connector at this price
- Fully modular, which is rare down here
- Capacity suits a mid-range card with headroom
- Warranty is shorter than the premium units
- Audible under sustained heavy load
(opens Amazon in a new tab) - Band
- $$ Mid tier
be quiet! Pure Power 12 M
The quiet option at the budget end, from a company whose whole reputation is noise.
- Noticeably quieter than most units at this price
- Modular cabling keeps a small case tidy
- Sensible warranty for the money
- Fewer connectors than some rivals
- Costs a little more than the cheapest credible options
(opens Amazon in a new tab) - Band
- $$ Mid tier
Corsair RM750e
The unit to stretch for if the budget can be persuaded to move at all.
- Long warranty for a unit at this price
- Fan stops entirely under light load
- Headroom for a graphics card upgrade later
- Above what most people mean by budget
- Cable set is functional rather than generous
Questions people ask
Is a cheap power supply actually dangerous?
A genuinely bad one can be, and the category is unusual in that the worst products are not merely disappointing. A unit with inadequate protection circuitry can fail in a way that passes the fault along to the components attached to it, which turns a cheap purchase into an expensive one. The units worth buying at the budget end are the ones from established manufacturers with a real warranty behind them, and the ones to avoid are the unbranded units whose stated capacity is not backed by anything you can check.
What is the cheapest safe wattage?
There is no universal answer, because it depends entirely on the graphics card you are pairing it with, and the graphics card is the largest and spikiest load in the machine. What is universal is the method: add the card manufacturer figure to the processor figure, allow roughly seventy-five watts for the rest of the system, and then buy above that total rather than at it. Buying the smallest unit that theoretically fits is how people end up with a machine that shuts down in one particular game.
Is a non-modular supply a false economy?
Not on cost, but often on outcome. A non-modular unit is cheaper because every cable is permanently attached, including the ones your build does not use, and those cables have to be stored somewhere inside the case. In a large case with a cable compartment that is merely untidy. In a small case it becomes an airflow problem, because a bundle of unused cables sitting behind the front intake is a wall in the path of the air the machine needs.
MSI MAG A850GL
Real capacity, modern connectors and full modularity at a genuinely budget price.
