That is interesting, because I haven't been able to get a clear picture of that.

I saw some Youtube comparisons of the same or similar (gaming) laptops where one has some new Intel CPU, and the other a similarly specced AMD Ryzen CPU, and both had the same NVidia GPU.

The impression I got from those was that Intel CPUs start throttling sooner ie. in lower temperatures, while AMD allows its CPUs to run hotter before it starts throttling. I don't recall the figures but when they inspected the temperatures, something like the Intel CPU would start throttling at 85C degrees, while AMD allowed its CPU to run at 92C (just to give some idea of the difference, as said I don't recall at which temps the CPUs really ran in stress tests).

So I wasn't sure what to make of that. AMD Ryzen can be faster because AMD starts hot-throttling it later than Intel? Is that still safe, without my laptop bursting into fire?

Anyway, I guess it depends how much power each CPU uses; generally a lower power consuming CPU should generate less heat as well... but I am unsure if that can be compared directly between different CPU families.

Mainly the comparisons seem to be between M1 Mac laptops against earlier Intel-based Mac laptops, like:

https://techcrunch.com/2020/11/17/yeah-apples-m1-macbook-pro-is-powerful-but-its-the-battery-life-that-will-blow-you-away/

Yes, I've actually looked at that review.

I've no hard numbers to back it up, but I've gone through a considerable number of laptops at work, and a couple at home, and the fan noise and battery life of recent Ryzen mobile chips were like night and day when compared to Intel CPUs.
Both in casual use and when doing long running, intensive tasks.

Never felt a need to measure it as the difference was so huge as to leave no doubt of the winner.

Specifically about my Envy x360, it's been a while so I can't be sure, but I seem to recall that part of the reason for the Envy staying so cool and quiet is HP running the CPU at a lower wattage than it's actually rated for, whereas Lenovo had chosen to run their 4700u and 4800u CPUs at full tilt.

I chose the HP because of this. (And also partly because the latest T14 ThinkPad I tried at work suggested Lenovo no longer gave a flying 4X about build quality.)
The HP is still plenty powerful, and 90+% of the time the fan is off.
Despite only having integrated graphics it can still run Shadow Tactics at 1920x1080 at max settings. Though of course the fan switches on fairly soon.
Simpler 2D games (e.g. Day of the Tentacle) do not activate the fan or only has it running at the lowest speed where I'm hard pressed to hear it.
The PC only ever gets lukewarm.
This is with "HP Recommended" settings, balancing performance, noise and temperature. Other profiles are available.

For about the same price as the Macbook Air M1 8GB, I got twice the RAM and twice the disk space as well as a touch screen.

That said, the M1 is damn impressive and the Rosetta 2 x86 emulation is very, very good.
The screen is fantastic (but non-touch), battery life is unprecedented, and having the laptop switching on instantly, not after a second or two, but instantly as an phone or tablet when opening the lid is amazing.
I'm not a fan of MacOS and actively hate their keyboard layout, but I would still have gone for the 8GB Macbook Air if I felt I could trust Apple not do deprecate the emulator after a couple of MacOS upgrades, leaving it unable to run GOG games.

For mobile use, the M1 beats anything Intel and AMD have on offer, IMHO. But Apple being who they are with their consumer and developer hostile history of breaking backwards compatibility seemingly just for the hell of it, I have to stay in the x86 fold for now.

Like when Apple discontinued the Apple 2 series and didn't provide any backwards compatibility?

More good news for the Deck and more importantly Linux gaming:

https://wccftech.com/amd-fsr-can-be-applied-to-all-vulkan-games-via-protons-fshack/

You can now get AMD's FSR working on pretty much all modern games (native Vulkan, or DX9-11 on DXVK and dx12 on vkd3d-proton). But only on Linux.

Digital Foundry put out a very interesting discussion about the SteamDeck: DF Direct Special: Steam Deck - Spec Updates, Performance, SteamOS, Compatibility

However, what I found eye opening is that while Valve said that you could install Windows 10 if you wanted, the problem is that Windows 10 wasn't build around the ONE thing that is critical for all handhelds: the ability to turn them on and off at the press of a button, while inside a running game. So Windows 10 will never be an option as a full-time OS for the SteamDeck!

Which means that you are stuck on SteamOS, unless they develop it to handle a boot loader, in order to install multiple OSes. So if you intend to play PC games on the SteamDeck, you are completely dependent on STEAM's continued support for the SteamOS and ProtonDB. And this is why everybody is talking about Valve's track record of handling hardware they released.

Another interesting point they touched on, most non-native games working on SteamOS, are new DX11-D12 games. Older, DX9 and lower games are a gamble.

You mean like you can with any win 10 laptop?

Sleep mode should allow you to do that; just replace "press a button" with "close (or open) the lid" and it should work, if the game is well behaved.

With that said, the issues with Windows 10 on this thing are as follows:
* Most likely, this device will *not* come with a Windows 10 license, so you'll have to pay for it (or pirate it).
* I believe 64GB is not enough space for Windows 10 to be comfortable; you may run into the situation of updates failing due to a lack of space.

Shut the lid. Open the lid 10hrs later. Continue the game.
Well of course it wont. (edit: that sounds snarkier than intended)

Technically though you never have to activate windows 10 - the morality and ethics of which I'm not going to talk upon here - but theres no need to pirate it.

That said, plenty of people seem to buy the licences anyway and transfer them between one machine or another as they go through them (ie "this laptop is beyond use").

They are talking about it at around 46:30, so it's not something that I imagined. They wouldn't be talking about it if it was as easy as "close the lid".

Personally I've never tested how a running game handles "sleep-recovery from sleep" on Windows/Linux.

I have. Through daily use So I've no need of even looking at your link, nor any interest in doing so.

You've tested suspending a game by closing the lid and allowing the laptop to go to sleep, and recovering that game state from sleep... DAILY?

You're the one that responded to my comment, and now you say you have no need or interest of looking at my link? Where is this aggression coming from? When did I ever shit in your feeding bowl? Did somebody get the monkey man drunk again?

heh sleep mode is very quick and gets you back where you started , except some online stuff but that is understandable