A home theatre PC for streaming 4K video, a small form factor PC for browsing and gaming, or even a workstation for light editing and Microsoft Office, are all cases where a 450-watt PSU will more than suffice to power the system’s hardware.
Choosing the appropriate amount of wattage for such operations may be simple, but actually choosing the PSU model for your needs could be a bit more complicated than expected. There are several key aspects to keep in mind when purchasing a PSU, as it is an important component that will stay with you irrespective of any other hardware upgrades you choose to make.
The first, and perhaps most important, aspect to take into account when purchasing a PSU is its thermal efficiency. The more energy efficient the PSU, the less it will cost you to operate your PC, and the less heat that will be released into the system and its included hardware. This is particularly important for SFF PCs, where the hardware is cramped into a tight space and overheating can easily become an issue. That being said, the more efficient the PSU, the higher its initial cost, so you may want to invest into the proper efficiency depending on your intended use.
If you plan to use your PC for occasional gaming a few hours a week, then you won’t need the same PSU efficiency as someone who plans to use their rig for eight-hour workdays. It is also important to note that the standard certification for PSU efficiency, the 80 Plus rating, tests each unit in open air under room temperature, so any resulting heat from other PC components is not taken into account. Since this additional heat will diminish the efficiency of the PSU, if you are looking to build a small form factor PC you are going to want to aim one category above what you would normally get, in order to account for the increased temperatures.
Another aspect of the PSU that can quickly become annoying, especially if you use the PC often, is the noise output. Having to deal with a constant humming or buzzing noise for multiple hours a day can really become aggravating. If your PC is to be less than a few feet away from you, then you will want to make sure that the PSU you purchase has minimal noise output.
Finally, another important aspect is the PSU’s cable management. You will generally want a PSU that is at least semi-modular, meaning that most, if not all, of its cables can be removed, so the cables you don’t need can be removed, instead of having to cram them inside the case.
To help you find a suitable power supply for your next setup, we’ve compiled a list of 450W PSUs for several different 80 Plus certifications; starting from White (the base 80% efficiency needed to qualify for 80 Plus) all the way up to Platinum. In addition, we have also selected the best SFX-L 450W PSU available for SFF PCs.
Best 450W Power Supplies – Our Recommendations
Best White Rated 450W PSU
A PC that will only see limited will usually need no more than the efficiency guaranteed by the regular 80 Plus certification – especially for low-wattage PSUs like the 450 in question.
The Cooler Master MWE is a standard ATX sized power supply with an 80 Plus white certification; meaning you’ll have at least 80% efficiency from this unit. What’s great about this PSU is that it has a single +12V rail which outputs 444W of power, so you can rest assured that your hardware will receive the appropriate amount of wattage.
To ensure that the PSU does not make unnecessary noise, the 120mm fan included is equipped with hydro-dynamic bearings, and will only operate depending on the temperature of the PSU. Therefore, the fan will not spin at all under low to medium loads, and the power supply will operate silently. The only questionable aspect about this PSU are its cables. The flat black cables are meant to take up less space for easier cable management, but the lack of sleeves or other material reinforcement may make them more prone to cuts and tears. Having thinner cables will surely reduce the clutter, to a certain extent; so, as long as caution is taken while installing the PSU, this should not be much of an issue. Do note that the MWE 450 is not modular.
If you’re looking for an entry or budget level 450W PSU, then the Cooler Master MWE 450 White will suit your needs sufficiently. You can currently purchase this PSU for $56 which, given the circumstances and existent PSU shortages, is still a great price.
Best 450W Bronze Rated PSU
Going up a notch in terms of efficiency, we have the Bronze certified Corsair CX Series 450M. Corsair is one of the leading manufacturers of PSUs, and their power supplies set a standard for both quality and durability.
The Corsair CX 450M, in particular, is no different. It has a single +12V rail for reliable power output and a thermally controlled fan which operates depending on the temperatures of the PSU. This 120mm fan also makes use of rifle bearings, which are quieter than ball bearings, yet have just about the same lifespan. In addition, during low to medium loads the fan will not operate, so the for the most part the PSU will be silent. The cables included with CX 450M are fully-sleeved, so they have an extra layer of protection. The PSU itself is semi-modular, meaning that the peripheral power cables are not hard-wired to the PSU, and you can add them depending on your needs. One last thing to mention is that the CX 450M has an over/under-voltage, over-power, and short circuit protection so that you don’t have to worry about any potential electrical damage to your hardware.
When available, you can find the Corsair CX 450M for $69 – which again is a great price, all things considered.
Best 450W Gold Rated PSU
Going a step up in the efficiency category, we have the EVGA SuperNOVA 450GM: a PSU suited for small form factor setups that require efficiency and full modular capability.
With the 80 Plus Gold certification, the SuperNOVA achieves efficiency upwards of 90% at typical loads; which is particularly useful for SFF builds where the less heat generated from the components, the better. The +12V rail can output the full power capability of this PSU, (up to 54.1A on this single rail), so you don’t have to worry about insufficient power being an issue. The fan on this PSU is 92mm in diameter, with double ball bearings for a better thermal and acoustic profile. Like the two aforementioned PSUs, the SuperNOVA 450GM’s fan also operates automatically depending on the system load and temperature of the PSU.
Another plus is that the PSU is equipped with all Japanese high-quality capacitors, and the reliability of this PSU is guaranteed via EVGA’s included seven-year warranty, and excellent customer service. One last thing to mention is that despite the SFX size of this PSU, it includes an ATX bracket adaptor so that you can use it on any type of PC case. You can currently find the EVGA SuperNOVA 450GM for $95; down from its original $109 price tag.
Best 450W Platinum Rated PSU
We return back to Corsair for the top-echelon of quality and power efficiency: The Corsair SF450W 80 Plus Platinum PSU.
The 80 Plus Platinum translates to a 90%, 92%, and 89% efficiency at 20%, 50%, and 100% loads respectively (92%, 94%, 90% for 230V EU variants). With such a high level of efficiency, you won’t need to worry about any thermals emanating from your PSU, so it is optimal for a small form factor PC.
Other than the higher 80 Plus rating and the 105-degree Japanese capacitors featured by this PSU, it is in all other ways similar to the aforementioned CX 450M. It is fully modular with individually sleeved cables, it has a 92mm fan that operates depending on the PSUs current load, and like the EVGA 450 GM it also comes with an SFX to ATX bracket adaptor.
Purchasing the Corsair SF450 will currently cost you $124 on Newegg, but $154 from Amazon; so be on the lookout on deals for this excellent Platinum-rated PSU.
Best 450W SFX-L PSU
And now, the truly remarkable SFX-L PSU, SilverStone’s NJ450: an 80 Plus Platinum power supply optimized for small form factor PCs.
What’s most incredible about the NJ450 is the fact that it completely discards the fanned PSU design. Being without a fan means that there is zero noise produced by this unit, and due to its passive cooling thermal solution it still operates at only 40-degree Celsius. This is achieved via an extruded aluminum shell that has a stacked fin design (similar to a heatsink), allowing the thin metal fins, which are designed to maximize exposure to cooler air, to absorb and dissipate the heat. Needless to say, this design will work optimally within a case that has a decent amount of airflow to push the warm air away from the fins. Another plus of the stacked fin design is that you won’t have to worry about dust build-up within the PSU and its inner components. Like the aforementioned PSUs, this power supply also has a single +12V rail that can output its full power potential. In terms of connectivity, the SilverStone NJ450 is fully modular and comes with a total of 18 connectors.
If you’re looking to build a powerful small form factor PC that will last for many years to come, then the SilverStone NJ450 offers unparalleled quality and performance, especially with its 80 Plus Platinum efficiency and 0 dB acoustics. Of course, this luxury does come at a price – namely $170 – but it’s well worth the cost for a PSU that you can rely on for several future iterations of your setup.