The solid-state AirJet cooler, “unlimited by the constraints of mechanical devices,” aims to double its thermal capacity every two years. You know, Frore’s law

In 2023, Frore Systems caused quite a stir when it announced its fanless AirJet cooler. It is a solid-state cooling solution that uses an innovative ultrasonic vibrating membrane to move air in a much smaller package than a traditional fan system. While it’s been touted as a potential next step in cooling design, at least for small cases, I have my doubts about the AirJet. The lack of adoption and similar lack of significant media coverage since then is not a very positive sign.

At Computex 2024, I had the opportunity to see the latest version of Frore AirJet Mini Slim. I also had the opportunity to speak with Frore Systems CEO Dr. Seshu Madhavapeddy about the scalability, applications, and performance the new models can deliver.

Surrounded by various devices equipped with AirJet Minis, one of my first questions was about noise. This may be a popular theory, but at first I assumed that the lack of adoption would be about how much noise the airflow would produce and whether a high-pitched squeal or similar problem might be holding it back. I asked Dr. Madhavapeddy if I could hear the air moving up close at full tilt.

“Of course,” he replies. – You’re surrounded by them now.

While various Macbook Airs, iPhones, and similarly thin devices around me wore transparent cases to show off the AirJet inside, I assumed they were idling given the lack of fan noise in the room. I took the laptop and put it to my ear, and sure enough, during the benchmark test, it pushed out a decent amount of hot air – and the noise was only audible a few inches away. Even then? Surprisingly quiet.

Three Frore Airjet Mini Slims mounted in an Apple Macbook Pro with a transparent panel

(Image source: Future)

Granted, this was in a conference room at the Nangang Exhibition Center, so background noise was absolutely a factor. However, with no noticeable whine or noisy rush of air even at close range, the AirJets I saw operated much quieter than I expected at maximum efficiency.

Additionally, comparison charts show significantly better performance results for AirJet-equipped chips compared to models equipped with traditional cooling systems or passive solutions. So if the performance is impressive and my personal noise theory has been debunked, why haven’t we seen AirJet features in more devices?

We are not limited by the limitations of mechanical devices in terms of increasing their power

“When you do something as groundbreaking as we do – we’re essentially creating an entire supply chain and a production line on top of that – it’s a very complex product that we’ve built using completely new materials and manufacturing processes,” explains Dr. Madhavapeddy.

“So, you know, I’d like you to be a little patient.”

Rightly. But the products I was shown looked – and felt – like production units, not prototypes, and the room was full of them. I asked how much Frore was willing to produce?

“Millions,” Madhavapeddy replies with a smile.

Holding the AirJet Mini Slim in your hands and viewing media detailing its inner workings, it’s easy to see why such a small device with such a radical approach to air movement would take time to adapt to mass production.

The mechanism of the membrane layer inside the Frore AirJet, showing air being drawn in from the top and discharged at the end of the device

(Photo: Frore Systems)

An internal piezoelectric diaphragm vibrates at 24 kHz and draws air from the top of the device, disrupting the “boundary layer” of hot air above the chip being cooled beneath it, and then shoots it out through a thin vent at one end. This mechanism is said to be the key to AirJets’ performance in such a small device compared to a similarly sized conventional fan.

However, this fast-moving membrane gives the appearance of an easy point of failure. I asked if Frore had done any long-term testing on the durability and life expectancy of a single unit:

“We have gone through numerous reliability tests,” says Madhavapeddy. “We have been able to confirm that it will last approximately 10,000 hours of continuous operation. In a typical use case, this should last about five years.”

Although fans die all the time, I’d say it would be reasonable to expect a conventional fan to last more than five years. For example, the Noctua fan has a lifespan of over 150,000 hours. Still, given that the AirJet operates as a single, self-contained unit and provides an easy-to-open device that uses such a device, replacing it in the event of a failure doesn’t seem like too much of a task, and potentially easier than a conventional set of fans and heatsinks in a regular laptop.

Picture 1 With 2

Samsung laptop with a transparent panel showing several Frore AirJet Mini Slim devices placed under a copper plate — (Image source: Future)

Looking around the room, most of the demo devices had one thing in common: they were very thin, very light, and difficult to design around conventional fans. Given the device’s claimed performance, I wondered aloud whether I would eventually see several of them connected to a desktop processor. Hearing this suggestion, Dr. Madhavapeddy seems to flinch slightly:

“I think in desktops today, with this generation, we could help with spot cooling. For Gen 5 SSDs, if your primary fan-based cooling system is handling the CPU cooling, you can place one of them on top of an NVMe Gen 5 controller and be relieved.”

So it seems that as things stand, even a few AirJets can’t handle something like a modern, high-powered desktop processor any better than a good old-fashioned heatsink and fan. Still, the suggestion of a thin, efficient Gen 5 SSD cooler, compared to some of the sizable models I saw at this year’s show, seems like a tangible use case for the technology in its current form.

Up to this point, I was shown an external SSD with two AirJet Minis integrated into the case. The passively cooled version saw write speeds drop to 1,061.77 MB/s under long-term use, while the AirJet-cooled sample showed a sustained write speed of 3,153.98 MB/s.

Picture 1 With 2

External SSD with Plexiglas panel showing the installation of two Frore AirJet Mini Slim connected to the SSD — (Image source: Future)

About three times the performance is not to be regretted, although the casing could use some work. The prototype I was shown had exhaust vents placed on the side, which meant it blew uncomfortably hot air right where you put your hand to pick it up. A production model has been proposed with vents at the end of the unit, although I think it would take some getting used to with an external drive discharging large volumes of hot air, no matter how quietly and efficiently.

So the million-dollar question: given the inevitable R&D and production set-up costs, how much does the AirJet Mini ultimately cost on a per-unit basis?

“It makes sense,” says Dr. Madhavapeddy. But reasonable compared to the costs of producing a good fan?

we have several levers… greatly improving the heat dissipation ability of the chip

“NO. NO. But reasonable compared to the total cost of the product you buy as a consumer. We fit into the cost structure that can usually be incurred by anyone who produces this type of device.

“But if we compare directly with the fan, we will be more expensive. (Price) would go down with scale. It will also decline as our second and third generations will be more efficient.

“We wouldn’t expect costs to grow at the same rate as efficiency,” Madhavapeddy continues. “So the efficiency, or the cost per watt, will decrease with subsequent generations. In each generation, cost decreases with volume.”

Frore Airjet Mini Slim up close and held in hand

(Image source: Future)

When it comes to future development, the company’s credo seems a bit strange at first glance. This is called “Frore’s Law” and is a play on Moore’s Law, which in this case aims to double the thermal efficiency of the device every two years.

“We are not limited by the limitations of mechanical devices in terms of increasing their power,” says Madhavapeddy. “We could increase efficiency by increasing the vibration frequency, and we could also increase efficiency by increasing the (vibration) amplitude.

“So we have some levers that we can continue to refine to significantly improve the heat dissipation ability of the chip.”

It’s an ambitious goal that seems more than a little impossible. That being said, the units I’ve been shown seem much more launch-ready than I expected. If they can really increase their performance at this rate, it seems like there will be greater adoption.

While the AirJet Mini Slim may not be the solution to all your cooling needs as it currently stands, it does seem to do a good job of moving significant amounts of air in shapes that aren’t suitable for a traditional cooler.

You won’t see it on a desktop computer anytime soon, at least on something significant like a GPU or CPU. But in ultra-thin laptops, tablets, phones and the like, or on an SSD? AirJet, at least in Mini Slim form, seems to be a ready-to-use product. However, whether mass adoption will occur or not, we will have to be a little more patient to find out.