If we move for a minute beyond the direct "hard" technical constraints which have already been expressed here (i.e. small chassis, lots of chips etc.).
You have a second aspect, the old PBCAK (Problem Between Chair And Keyboard) one.
Users will use their laptops in less than optimal (from a thermal perspective) ways. They will use it on their laps. They will use it in bed, resting on duvets. They will use it on pool-side sun loungers with the mid-summer sun blasting down. Yes you can tell them in the manual that they shouldn't, but they still will.
So even if you can magically cool the chips passively, the possible use-cases of the product might ultimately constrain your ability to forgo a fan entirely.
I note that some people here are seeking to blame the "race to thin" for the requirement for fans. To them I would merely point them at the Panasonic Toughbook. Modern laptop but built like an old-shool 90's brick ... it still has a fan.[1]
Apple have done a stunning job with the M1 (and previously with the i5/i7). But even with the unibody chassis of a MacBook (i.e. the whole device is a massive heatsink) the necessity of forced cooling is still there (edit to add: with the exception of the MacBook Air M1 ... thanks for the correction guys !) . But with the non-Air M1s you really have to work super hard to make the fans ramp up at all, they've done a stunning job.
But it's not just laptops that lose their fanlessness (which I appreciate both due to noise and reliability concerns), but also NUCs - almost every single NUC-like device that has entered the market and managed to come to my attention over the last months has had a fan installed. I wonder why that is - TDPs do not seem to have gone up, at least not when looking at data sheets... maybe it's just cheaper to make stuff that way.
Tablets mostly spend their energy budget (under normal operation) on illuminating the screen and most of the action content they see would either classify as webpages or video encoded with codecs they have hardware support for decoding efficiently.
A generic PC meanwhile runs a heavy OS and is often asked to do large volumes of local processing tasks. E.G. that bloody 16GB Outlook mail database that has to be stored locally because your power user that demanded a laptop has to be able to read all of their past email while they're in the field with no reliable net connection.
Oh, they also demand that it has to be light. Fans are cheaper and lighter than putting enough metal inside to do something passively; and also run cooler since even a pathetic volume of airflow is many times better than waiting for convection alone to move the heat.
You can blame the noise of the fan on the push for crazy flat laptops though. There's no reason a still light but thicker laptop couldn't use a larger slower moving fan. Well, other than the perception of thick as heavy and thus bad.
I bought my Asus UX305C about five years ago now. It's fanless, and the CPU is definitely a little slow, because it's an Intel atom. However, I wasn't buying it for the CPU - I was buying it for the fact that it was fanless, had a decent keyboard, hidpi screen, enough RAM, and sturdy metal case. I don't need a fast CPU, because everything I do is run on a chunky server somewhere else. It feels like an expensive laptop because of the metal case and nice screen.
I was so pleased with it that I recommended an Asus laptop to someone else, but unfortunately that one does have a fan, and the case is made of plastic, and it feels really cheap. The touchpad stops working properly when you hold the laptop case in a particular way, which bends the plastic and stops it being able to detect fingers.
I think it doesn't matter much, as you can take a standard laptop and restrict the clock speed, and the fan will never turn on.
I've been buying dozens of those for people at work since 5 years now (first ones with n5000) and I still have to hear a single complaint about it.
The only point of failure of that thing is the charging port, proprietary, not usb c.
I don't have any first-hand experience with this (yet), mind you, and am unable to comment on other features :)
My work laptop is one of those macbook air style super light Windows ones, I thought it was fanless until I watched a teardown, the fan hardly turns on and I have to put my ear to hit to hear when it does.
> Is it impossible to passively cool i5, i7 (integrated graphics)?
Obviously not, but same as with the M1 in the air and in the pro: fan=more power and heat available. Add the fact that in many devices you have to try really, really hard to be even able to hear the fans adding them is a no brainer.
I think most surface pro lineups had the i5 being fanless and the i7 with a fan. And that was a problem, because although the performance difference between the i5 and the i7 wasn't that great (most would not pay for the difference) the cooling differences made it night and day. And as someone who loves passive cooling I was forced to recommend the i7 just because it had a fan. (note: in latest lineup of the surface pro the i5 also has a fan, making the i5 version much more attractive for most (though now it cost as much as the i7 used to do ...))
There is a huge difference in cooling between passive and a very very slight breeze, intel/amd CPUs are a bit too hungry for it to make much sense in the medium-to-high performance CPUs. Though I feel not enough attention is being put into cooling of laptops (passive nor active), isn't a strong selling point I guess (though it should!).
No it is not.
Why do they not sell one? Because passively cooled x86 CPU doesn't run every fast enough (yet) which leads to poor sales number.
May be a few more years. When both IPC and node improvement catch up.
other than that, everything else I find has weak Celerons in it.
You could go "fanless" on many laptops, though. You'll have to check beforehand, but all you need is TDP adjustment (and ideally, undervolting) support and the ability to turn off the fan or adjust the speed table with something like NotebookFanControl.
For TDP/TPL/voltage adjustments, use Throttlestop on Windows; Linux also has some tools or you can write to MSRs directly after a long night of figuring them out. AMD mobile chips can not be undervolted as of right now, btw, a real shame. But neither can Intel with Plundervolt mitigations, so that's a double real shame.
A Core i7 can go up to ~20W without turning the fan on, and higher with the fan at minimum (I doubt you'll hear it). The critical temperature (=fan at full speed, overriding settings) is usually over 80 degrees Celsius, which is high enough that it may never get there.
Using better thermal paste would be highly desirable, too.
The major disadvantage is obviously performance - you'd get half of whatever the chip offers, at best.
More laptops should have fanless modes, where the processor is power limited & only passive cooling is used. I believe this would be possible on many laptops. Perhaps especially gaming laptops could potentially do very well only on their passive mode while not gaming, since they have such a large focus on cooling, but given the extreme flexibility in specifying power limits for chips that's possible these days, I feel like quite a wide range could have a pretty ok passive cooling performance.
It's be wonderful if there was a good standard review process to better explore laptop noise. That seemingly is the objection to fans, yes? Rather than totalize the ask, allowing different routes to success would imo be preferred.
With the fan off it sits at 65°C vs 55°C fan on when browsing the web and programming. It only approaches 80°C (threshold at which the fans engage) when viewing Google Maps or gaming.
I suppose I could make it run even colder if I repasted it.
In any case now that Apple isn't using TSMC's entire 5nm capacity anymore we should expect nice, fanless laptops to become more common. Lenovo recently released the X13s, which has the Snapdragon 8cx and glorious 20h+ battery life. The M1 Air is still faster, but some of us refuse to use their hardware and this device fills this niche.
So what I'm hearing is that you don't want the devices that are already on the market, probably because you think they're underpowered.
If nobody is buying the existing devices, why would they make more varieties?
My i9 mac just makes me angry, every time docker spins up. Stuck with it for a few more years as we start going into the office.
I do run Linux, and have a fairly light-weight environment (dwm etc.) I don't know how much that matters.
My opinion is intel/amd are not incentivised to make silent / fanless designs as they are hard to market as they are not going to be the fastest. Apple are incentivised as a silent cool running computer is something people will buy.
On the other end, it generally takes a couple of iterations to get a fan-less design right, because you can't simply slap an oversized heatsink into a mobile device.
See: https://www.ofzenandcomputing.com/best-fanless-laptops/
part of the date is rechecking assumptions as sometimes we do not re-check them ourselves before posting.
People preferring fanless/quiet devices are a minority and devices made for them won't sell enough to justify the design costs.
Also, latest Intel CPUs can eat up to 300W for some reason.
I was really disappointed with the fan behavior of my Thinkpad X1 Nano -- constantly spinning, and loudly. I use third-party software to control it now. Having the fan spin for writing an email is just ridiculous.
Because, to cool passively, they need huge heatsinks.
Real passive machines are in 15W limit, but commodity x86 are 25W and more.
Military notebooks are passive, but they used all their case as huge heatsink.
Why are you still wondering is the real question here.
The more power any electronic device uses, the more heat it produces.