Cold Test Results

For the testing of PSUs, we are using high precision electronic loads with a maximum power draw of 2700 Watts, a Rigol DS5042M 40 MHz oscilloscope, an Extech 380803 power analyzer, two high precision UNI-T UT-325 digital thermometers, an Extech HD600 SPL meter, a self-designed hotbox and various other bits and parts. For a thorough explanation of our testing methodology and more details on our equipment, please refer to our How We Test PSUs - 2014 Pipeline post.

The Corsair CM450M makes a borderline pass through our efficiency test, just meeting the standards required for 80Plus Gold certification. The energy conversion efficiency reaches 92.1% at 50% load. An average conversion efficiency of 90.2% is achieved within the nominal load range (20% to 100% of the unit's capacity). It seemingly does not perform very well at very low loads, with a conversion efficiency of just 76.1% at 5% load. That however corresponds to an actual load of just 23 Watts and more powerful units would likely fare far worse at so low a load. With a load of 45 Watts, a fairly reasonable figure for the idling state of an average home PC, the conversion efficiency jumps to 83.5%.

As the power output of the CM450M is low and the conversion efficiency is high, it does not have high cooling requirements. Our testing results are not surprising, as the little 450W PSU maintains very low operating temperatures even when heavily loaded. The cooling fan does remain inaudible across most of the load range but it increases its speed at higher loads, reaching audible (but not intrusive) figures. 

The Corsair CS450M PSU Hot Test Results
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  • jann5s - Wednesday, June 10, 2015 - link

    +1 on "Thanks for reviewing more a more reasonable PSU!"
  • alin - Wednesday, June 10, 2015 - link

    I agree!!! Thank you for this review and others like this.
  • DanNeely - Wednesday, June 10, 2015 - link

    "With the exception of the sleeved ATX cable, of the cables are "flat", ribbon-like, with black wires."

    I've seen this in a number of other PSUs and it's always annoyed me. IMO the main functional advantage of flat cables is that they're easier to bend for routing purposes; but 6/8 wire round cables are still relatively easy to manage. The bloated dinosaur that's the 24pin ATX cable is another story entirely and getting it through tight spaces or sharp bends is a major pain.
  • meacupla - Thursday, June 11, 2015 - link

    I like ribbon cables, but I don't like the 90deg sata connectors found on some of them.

    The bending and stress on the cables ends up being worse than straight connectors, as the distances between connector vs. the distance between drives is never a perfect match.
  • romrunning - Wednesday, June 10, 2015 - link

    Thanks, E., for your review of a decently-sized PSU for a regular budget build! It's really nice to see a review that I can actually use.

    I would second the comment that it would be nice if you were able to get a retail unit or two to see if it scores similarly to the review unit you were provided. Perhaps Purch can provide a monthly allowance for the retail purchase of units to ensure review units aren't just cherry-picked for the reviewer.
  • romrunning - Wednesday, June 10, 2015 - link

    Typos - the conclusion erroneously calls this model the "CM450M" a lot.
  • hans_ober - Wednesday, June 10, 2015 - link

    Nice review!
    Would be nice if you could do a roundup of cheap 300-500W PSU's
    Antec, EVGA, Seasonic, Corsair + a crappy one (for fun).

    A roundup of competing products would be nice
  • YoloPascual - Wednesday, June 10, 2015 - link

    Corsair should sell this at 50-60$, at 80$ it is eaten by the competition.
  • rocktober13 - Wednesday, June 10, 2015 - link

    I purchased one earlier this year for a home server for $40 after rebates ($60 with $20 mail in rebate). This model is always on sale with mail in rebates from newegg. I have seen it as low as $35. I was skeptical about the performance, but after the review it looks like great value. Thanks for the very useful review.
  • JesusVanDam - Wednesday, June 10, 2015 - link

    The CS450M only provides 1 6+2 pin PCI-E cable? That's really disappointing. I'm running an R9 270 and it requires 2 6 pin cables.

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