I tested one of the most popular laptops cooling pads, and it’s the first ever to outright flunk our chilling test

Klim Mistral: review

The Klim Mistral is a mid-market laptop cooling pad that has proven particularly popular on online retailers such as Amazon. While it had an original list price of $86.97 / £74.97, shop around and you can pick it up for less, with even Klim selling it direct for $69.97 / £59.97. This seems a pretty decent outlay, especially given it rocks pretty hardcore 4500rpm fans. But how did it perform in practice?

First off, I was pleasantly surprised by its aesthetics. As I remarked in my Klim Wind review, I wasn’t all that enamored by the look of that cooling pad – I still stand by my assessment that it looks like a "cyber-goth butterfly". By contrast, the Mistral is more mature-looking, dropping some of that edgy gamer styling for a cleaner silhouette and a five-color LED light strip – although the latter is cheaper-looking than some, clearly just showing 10 separate RGB LEDs.

There are also plenty of design touches that would imply it offers more professional cooling. For example, it comes with a rubber seal around its rim that will create a high-pressure area designed to force cooling air into your laptop's fans, maximizing their effectiveness. In addition, Klim has supplied heat shields to redirect air flow should your laptop also vent from the rear as well as from beneath; our testing Acer Predator Helios 300 laptop with an Nvidia GeForce RTX 3080 GPU sits firmly in this camp, so I dutifully applied them.

When it comes to ergonomics, the Mistral offers a good range of height settings, offering six in total. The top 29-degree angle is too steep to use the keyboard comfortably, but spot-on if you’re just using the screen, while the lower 19-degree angle felt comfortable for long typing sessions. Conversely, I found the placement of the laptop rests to be a bit uncomfortable – they’re easy to adjust to the height of your laptop, but since they stick up above the lip of the wrist rest, I found they dug into my wrists. However, I find this is a problem with a majority of cooling pads.

So it’s safe to say that after experiencing this mindful design, my expectations of the cooling the Mistral would offer was quietly optimistic – or maybe even loudly optimistic, once I’d seen those two enormous 4500rpm fans built-in. Unfortunately, my hopes were dashed more thoroughly than a college student’s AI-written dissertation.

As always, I tested the Klim Mistral’s cooling capacity by running a 3DMark Steel Nomad stress test on our testing laptop for 15 minutes with the cooling pad on max power, measuring the device’s temperature before and after. During the test, our laptop rose from 77ºF / 25ºC to 113.9ºF / 45.5ºC, a whopping 36.9ºF / 20.5ºC – for context, we’ve only had one cooling pad perform worse, the $29.99 / £29.77 TopMate C12 Laptop Cooling Pad, which presided over a rise of 41ºF / 22.8ºC. That’s significantly below what I’d expect from a cooling pad at this price.

In fact, I was so baffled that I did something I never do: I gave the Mistral a second chance. I re-ran the test later in the day, in the event that user error had somehow contributed to this poor performance. Ensuring the laptop was sat firmly on top of the seal, I found the results were certainly different – but not in the way I’d hoped. This time, the laptop’s core temperature rose a ludicrous 54.9ºF / 30.5ºC. Given our baseline stress test for our laptop only saw it rise 57.4ºF / 31.9ºC, this would mean the cooling pad shaved off only 2.5ºF / 1.4ºC, which is negligible enough not to be worth the trouble.

Trying to give Klim the benefit of the doubt here, it does warn heavily on its website that only certain types of laptop will work properly with the Mistral. Your computer will need to be between 15 and 17 inches and feature downward ventilation – but our testing laptop did meet both these criteria. I have also seen several online user reviews mention that the design of their laptop meant there were still small gaps around the rubber seal, negating the high-pressure effect intended.

Still, even if the Mistral's poor performance is down to the fact our laptop isn’t the perfect fit for its design, most of the other cooling pads I’ve tested have functioned regardless of the shape of our testing device. Sure, it’s perfectly possible that the Klim Mistral will send a chill through your laptop more icy and severe than your second-grade teacher – but do you really want to roll the dice on that?

Another thing that Klim warns about on its site is that its supposedly high-performance design can result in a lot more noise. If I’m honest, it didn’t really strike me as much of an outlier here: measuring the combined noise output of the cooling pad and our laptop 10 minutes into our test, it clocked 61dB from a few inches away and 51dB at my head height. That’s pretty much par for the course for medium to high-end cooling pads, so it wasn't really a concern. If you're a bit more noise-sensitive though, you may find your mileage here varies.

Ultimately, I feel like the Klim Mistral’s build and price write checks that its cooling can’t quite cash. Yes, I’ll accept that it might achieve better results if you have the exact design of laptop – but is that something you should really have to take a punt on when spending $69.97 / £59.97? Fundamentally, other options on our list of the best laptop cooling pads offer more predictable performance, whether you’re spending this kind of money or much less.

Should I buy the Klim Mistral?

Buy it if...

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Klim Mistral review: also consider

How I tested the Klim Mistral

• Used it over the course of several days
• Measured the heat rise of a laptop with the pad on maximum settings
• Recorded how much noise it made two-thirds of the way through our stress test

To put the Klim Mistral through its paces, I followed TechRadar’s standard testing procedure. Running a 3DMark Steel Nomad stress test for 15 minutes on our Acer Predator Helios 300 laptop with an Nvidia GeForce RTX 3080 GPU, I set the Mistral on its maximum cooling and measured our laptop’s temperature before and after using a thermal camera. I then compared this to the benchmarks recorded from every laptop cooling pad test we’ve run to date.

In addition, I recorded the combined noise output of the cooling pad’s and our testing laptop’s built-in fans. To do this, I used a sound level meter to measure their volume 10 minutes into the test, recording it both from a few inches away and at my head height (21 inches away). This allowed me to get a sense of both an objective volume, as well as the subjective amount of noise you’re likely to experience in use.

Finally, I made sure I used the Klim Mistral in a variety of scenarios to get a sense of its ergonomics and how comfortable it was in use. I did this by using it to play multiple games and by using it for some of my daily work, so I could build up a meaningful impression of how it works in practice. I bring plenty of experience to this table: not only have I been covering gadgets for many years, but I’m also a creative and gamer, which means I have a lot of experience of pushing my laptops to their limits.

• First reviewed: September 2025
• Read more about how we test