 Have you ever had thermal issues with your computer and thought, Wow, if only I could get a bigger fan, I might be able to put my side panel back on. Well, if that's the case, we've got the fan for you and uh... This thing is powerful! Synergy allows you to share your mouse and keyboard between multiple computers at once. Check it out now at the link in the video description. So this one right here is the Delta PFR-0912XHE, let's call it the blowy Matron. And at $55, it is the most expensive blow I've ever gotten. I mean, this thing is almost four times the cost of even a high quality, normal consumer fan. So can it possibly deliver four times the performance? Well, funny you should ask. Try more like seven times the performance. Ramping up to a whopping 11,500 rotations per minute, in open air, Blowy Matron can push a staggering 90 liters of air every second. But how would we actually demonstrate what that means in real world terms? This thing not only spins faster than the engine of my Civic, it probably has more torque too. If you were to get your finger in this thing, well, to put it lightly, you're gonna have a bad time. Oh, disgusting! Oh, ho ho! That's what happens when you put your finger in one of these! Oh, we finally stopped it. Jammed full of carrot. So then with all of that blowing power, we started to wonder, well, what are the real world applications? So here's one. If you're really crunched for space in your case, at 37 millimeters tall, the super tiny Noctua NH-L9i is about as small form factor as you can get for a heat sink. But of course, that comes with some trade-offs. Mainly that you aren't supposed to use it on a high TDP, that is the thermal output, CPU. But there's the way it suggests in the manual, and then there's the Linus Tech Tips way. So can this heat sink cope with a fully clocked Core i7-7700K? Well, actually, it's a surprisingly resilient little bastard, and was able to keep our 7700K running at full turbo speed under synthetic load. Though it wasn't exactly comfortable at a maximum of 97 degrees Celsius. Fortunately though, our CPU won't have to run hot for long, since good ol' Blowing Matron is coming to the rescue. But how much of a difference does a seven times increase in airflow make for real world cooling? Well, Alex here is a great big cooling nerd. So the first thing we're gonna do is look at it from a theoretical standpoint. What is it that makes a heat sink remove heat from a CPU, and why does a bigger, better fan cool it more? To put it simply, there are three things that affect how much heat you can remove from your processor. The surface area that is responsible for cooling, the heat transfer coefficient of the process, and the temperature difference between the CPU and the surrounding air. Now it's intuitive that increasing the amount of air over a heat sink will make it cooler. Think about putting your hand out of the window of a car. You go faster, you cool more. But how much can upping the airflow help your cooling? So to figure out how big of a difference this is going to make, we have to calculate the convective heat transfer coefficient of air, or how much heat air can take away from an object, which is approximately equal to this formula, where H is the heat transfer coefficient, and V is the velocity of the air. So we know the knock to a fan pushes air at about one meter per second, and plopping that into the formula gives us an H value of 19.5, while Blowing Matron pushes air at 3.6 meters per second, giving us an H value of 25.8. But Linus, it's pushing the air 3.6 times faster. Why does it only make a 25% difference to cooling? Well, you see, I was math-ing the other day, and this one frigging square root over the velocity kept kicking my ass. You get diminishing returns the faster the air moves. So bringing it back to the real world then, can this be confirmed with the Blowing Matron? Well, with it strapped to our NHL9i under full load and Ida64, the CPU maxed out at 73 degrees Celsius, leaving us lots of room for overclocking, by the way. This also amounted to about 30% cooler than the stock fan, close to our expected temperature reduction of 25%. And really, the LNG thermodynamics and precision pizza heating department considers anything within an order of magnitude a compelling victory. Of course, that compromised some of the space savings with our heat sink, leading us then to another question, this video really turned into kind of a voyage of discovery. What's better, having a cooling solution that's 3 quarters fins or 3 quarters a fan? Well, we tested it, and in this situation, the fan actually still wins in cooling performance per height. Although it isn't all hunky-dory, strap one of these guys to your heat sink, you're off to the races with a chilly CPU. First of all, there is power delivery. That stock Noctua fan sips 0.14 amps at full load. The Blowing Matron on the other hand, well, you probably don't want to attach this thing to a fan header on your motherboard, since it draws a whopping 4.5 amps at full load, which is nearly enough to overwhelm this bench power supply. And of course, there's also the noise. The Noctua fan puts out 24 decibels maximum, which is quieter than someone whispering in a library. Compare that to the 75 decibels of the Delta, which is more comparable to an alarm clock. Synergy is a software download that solves the problem once and for all of having two keyboards and two mice on your desk if you have more than one PC. It lets you share a single mouse and keyboard between two or even more computers seamlessly, so you'll no longer get confused about which one is connected to which. They offer a basic and pro option with a one-time payment for lifetime access. And the features include clipboard sharing between the computers, dragging and dropping files between the computers, the ability to set up hotkeys, and more. And the best thing is that Synergy is cross-platform. Wooo! PC, Mac, and Linux! So use our link in the video description to get up to 50% off Synergy today. So thanks for watching, guys. If you disliked this video, well, you must be in the, like, banana protection league or whatever the case may be, because we ravaged that thing. But if you liked it, hit that like button, get subscribed, maybe consider checking out where to buy the stuff we featured in the link in the video description. And also down there, we've got our merch store, which has cool shirts like this one. Banana and carrot chunks not included, as well as our community forum, which you should totally join.