7X YOUR COOLING – 11 THOUSAND RPM FAN
Linus Tech Tips
·Linus Tech Tips
·2018-05-06
·
1,255 words · ~6 min read
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Have you ever had thermal issues with your computer and thought,
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"Wow, if only I could get a bigger fan,
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I might be able to put my side panel back on." Well, if that's the case,
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we've got the fan for you. And uh this
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thing is powerful.
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Synergy allows you to share your mouse and keyboard between multiple computers
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at once. Check it out now at the link in the video
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description. So, this right here is the Delta
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PFR912XH. Uh, let's let's call it the blowy matron. And at
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$55, it is the most expensive blow I've
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ever gotten. I mean, this thing is almost four times the cost of even a
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high quality normal consumer fan. So,
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can it possibly deliver four times the
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performance? Well, funny you should ask.
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Try more like seven times the performance. Ramping up to a whopping 11
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12,000 rotations per minute. In open
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air, Blow Matron can push a staggering
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90 L of air every second. But how would
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we actually demonstrate what that means
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in realworld terms? This thing not only
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spins faster than the engine of my Civic, it probably has more torque, too.
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If you were to get your finger in this thing, well, to put it lightly, you're
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going to have a bad time. Oh, disgusting.
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It's only getting on me.
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That's what happens when you put your finger in the leaf. Oh, we finally
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stopped it. jammed full of carrot. So then with all of that blowing power, we
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started to wonder, well, what are the realworld
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applications? So here's one. If you're really crunched for space in your case
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at 37 mm tall, the super tiny Noctua
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NHLi is about as small form factor as
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you can get for a heat sink. But of course, that comes with some trade-offs.
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mainly that you aren't supposed to use it on a high TDP, that is the thermal
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output CPU. But there's the way it
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suggests in the manual and then there's the Linus TechTips way. So, can this
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heat sink cope with a fully clocked Core
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i7 7700K? Well, actually, it's a
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surprisingly resilient little bastard and was able to keep our 7700 K running
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at full turbo speed under synthetic load. Though, it wasn't exactly
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comfortable at a maximum of 97° C.
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Fortunately though, our CPU won't have to run hot for long since good old blowy
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Matron is coming to the rescue. But how
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much of a difference does a seven times
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increase in air flow make for real world cooling? Well, Alex here is a great big
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cooling nerd. So, the first thing we're going to do is look at it from a
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theoretical standpoint. What is it that makes a heat sink remove heat from a
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CPU? And why does a bigger, better fan
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cool it more? To put it simply, there are three things that affect how much
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heat you can remove from your processor. the surface area that is responsible for
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cooling, the heat transfer coefficient of the process, and the temperature
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difference between the CPU and the surrounding air. Now, it's intuitive
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that increasing the amount of air over a heat sink will make it cooler. Think
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about putting your hand out of the window of a car. You go faster, you cool
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more. But how much can upping the air flow help your cooling? So to figure out
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how big of a difference this is going to make, we have to calculate the
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convective heat transfer coefficient of air or how much heat air can take away
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from an object which is approximately equal to this formula where h is the
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heat transfer coefficient and v is the velocity of the air. So, we know the
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knock to a fan pushes air at about 1 meter per second. And plopping that into
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the formula gives us an h value of 19.5
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while blowing matron pushes air at 3.6
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m/ second, giving us an h value of 25.8.
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But Linus, it's pushing the air 3.6 times faster. Why does it only make a
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25% difference to cooling? Well, you see, I was mathing the other day and
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this one friaking square root over the velocity kept kicking my ass. You get
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diminishing returns the faster the air
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moves. So, bringing it back to the real world then, can this be confirmed with
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the blowatron? Well, with it strapped to
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our NHL 9i under full load and ID of 64,
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the CPU maxed out at 73° C, leaving us
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lots of room for overclocking. By the way, this also amounted to about 30%
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cooler than the stock fan, close to our
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expected temperature reduction of 25%.
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And really, the LMG thermodynamics and precision pizza heating department
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considers anything within an order of magnitude a compelling victory. Of
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course, that compromised some of the space savings with our heat sink.
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Leading us then to another question. This video really turned into kind of a
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voyage of discovery. What's better, having a cooling solution that's 3/4
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fins or 3/4 a fan? Well, we tested it
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and in this situation, the fan actually
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still wins in cooling performance per height. Although it isn't all hunky
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dory. Strap one of these guys to your heat sink, you're off to the races with
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a chilly CPU. First of all, there is power delivery. That stock knock to a
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fan sips 0.14 amps at full load. The
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blowy matron on the other hand, well, you probably don't want to attach this
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thing to a fan header on your motherboard since it draws a whopping 4
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1/2 amps at full load, which is nearly enough to overwhelm this bench power
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supply. And of course, there's also the noise. The Noctua fan puts out 24 dB
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maximum, which is quieter than someone whispering in a library. Compare that to
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the 75 dB of the Delta, which is more
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comparable to an alarm clock.
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Synergy is a software download that solves the problem once and for all of
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having two keyboards and two mice on your desk if you have more than one PC.
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It lets you share a single mouse and keyboard between two or even more
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computers seamlessly, so you'll no longer get confused about which one is
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connected to which. They offer a basic and pro option with a one-time payment
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for lifetime access. And the features include uh clipboard sharing between the
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computers, dragging and dropping files between the computers, the ability to
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set up hotkeys, and more. And the best thing is that Synergy is
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crossplatform. Woo! PC, Mac, and Linux.
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So, use our link in the video description to get up to 50% off Synergy
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today. So, thanks for watching, guys. If you dislike this video, well, you must
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be in the like banana protection league or whatever the case may be because we
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we ravaged that thing. But if you liked it, hit that like button, get
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subscribed, maybe consider checking out where to buy the stuff we featured at the link in the video description. And
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also down there, we've got our merch store, which has cool shirts like this one, banana and carrot chunks not
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included, as well as our community forum, which you should totally join.