Temperatures, Fan Speed, and Acoustics


The two heatsinks remain at reasonable temperatures throughout testing. We've seen much worse results with other power supplies topping out at up to 90°C, so the worst result of ~54°C on the secondary heatsink is quite good. It reaches this point at about an 80% load, and then the fan speed increases and temperatures remain static up to 110% load. This indicates that everything is working properly and there shouldn't be any problems with long-term use of the power supply, and even if it's running at closer to 100% load.


The fan spins at a relatively slow 860RPM up to a load of 300W, at which point it begins to spin faster. It's at 1100RPM at 80% load (720W), and it no longer qualifies as a quiet PSU. Beyond 80% load, fan speed increases rapidly up to the maximum 2000RPM, keeping things cool as we have seen in the temperature graph, but your ears might not be as happy....


If your goal is to have a quiet or near-silent power supply, you will want to keep this PSU under 500W of load. Once we pass 700W, noise levels increase rapidly from 20dB(A) up to a maximum 31dB(A). Given the relatively tame temperatures, Cooler Master certainly could have lowered fan speeds and noise levels more, as the heat sinks are usually in the 40-50°C range. However, we won't complain too much as it will be quite difficult for most users to come anywhere near 100% load (or even 80% load) on this power supply.

Efficiency and PFC Conclusion
Comments Locked

33 Comments

View All Comments

  • JarredWalton - Tuesday, July 29, 2008 - link

    "We see very little voltage drop on the rails, which is very good. All of the rails are within 2% to 2.5% of regulation, starting slightly higher than the target voltage and dropping slightly below target at higher loads. Ripple on the 12V rails is also exceptionally good, measuring at most 8mV. Lower voltage rails also perform decently, though not quite as good, measuring up to 21mV. The ability of this power supply to deliver the required wattage with little voltage drop even at higher loads leaves us with a good impression."

    Posting a graph that shows ripple isn't really any more informative than what we did right there: up to 8mV ripple on the 12V rails and 21mV on the 3.3V and 5V lines. You might want to read the text a bit more closely before firing off complaints. We state in the conclusion that the PSU has very good ripple results, and I guess that's probably as far as you got? The previous several pages of test results are there for a reason.
  • Amart - Wednesday, July 30, 2008 - link

    A graph educates people, and shows that you've performed the necessary readings to construct it. Ripple/Noise is arguably one of the most important graphs to have on a review.

    Sure, you had 'something' in this review, which is an improvement over the last few months.

  • Christoph Katzer - Tuesday, July 29, 2008 - link

    With 78mV no company in the high-end field would have released the product...
  • mindless1 - Tuesday, July 29, 2008 - link

    Do you have any evidence that 78mV of ripple has caused any problems by itself, isolated as the variable? The powered parts themselves cause more than 78mV of ripple local to them, where it might matter if it ever did - this if you had a hypothetically perfect 0mV ripple PSU.
  • Zak - Tuesday, July 29, 2008 - link

    I found CM products to have competitive prices - but I don't shop for high end stuff - and I've always received their rebates.
  • nycromes - Tuesday, July 29, 2008 - link

    I too have only had good experiences with their products and rebates. I have heard that others have experienced problems with rebates, but I don't usually hear many complaints regarding their products.

    I guess that some people must get a different experience than others, the question is which one of us had the normal experience and which one of us got lucky. Until I have a bad experience, I am sticking with my Coolermaster products.
  • Glenn - Tuesday, July 29, 2008 - link

    You forgot to mention the business model coolermaster has relied on. Sell your product that has a worth of about $25 for retail price of $75 and then offer a $65 rebate that will likely not get paid!

    Then, when the customer has problems with the product, just make the process to repair or replace so difficult, that only the most persistant buyers will percivere the process to get something done!

    Hey, it must be working for them!
  • JEDIYoda - Tuesday, July 29, 2008 - link

    so what does anything you say have to do with this review?
    For that matter can you back up what your claiming with links??
  • Glenn - Tuesday, July 29, 2008 - link

    It has everything to do with any Coolermaster product review! If the company is poor on customer support, then it affects the value equation for prudent buyers. Sorry you don't understand!

    Do some reading-
  • JEDIYoda - Wednesday, July 30, 2008 - link

    I do understand very well! It is you that has a axe to grind against the Coolermaster products.

    The company support and how they handle problems has nothing at all to do with this review of the product!!

    Yoyr bitch is against the compant itself...the 2 are very seperate!!

    As usual a very well done review!!

Log in

Don't have an account? Sign up now