Laptop cpus might be able to sustain top clocks with proper cooling, but we'll never know.

Even SSDs throttle under heavy use.

> I mean, hardware wise they are not much faster, but cooling is a different story.

The highest spec macbook comes with a 9980HK and starts at 2800 $. A 3900X has approximately twice the performance in multi-threaded workloads and you can easily build an entire quiet workstation with it for less than 1000 $. Half the performance, thrice the price. Great deal.

Yes, there are also "laptops" with a 3900X in them. But even those still have lower performance than a desktop with a 3900X because of thermals.

There are obviously many ways to do this comparison, but going off Wikipedia's pricing for most recent Intel processors. Their highest end mobile processor is currently the i7-1185G7 which apparently retails for $426. Let's compare it with the closest desktop processor to that price, the i9-10900 ($438). Cores (Threads): 4(8) vs. 10(20). Base Freq: 3.0ghz (At 28w TDP) vs. 2.8ghz. Max All Core Turbo: 4.3ghz vs. 4.8ghz

Specs can never tell the true story, but it's clear that the mobile processor is going to be much slower for anything remotely processor intensive, and probably much more than twice as slow for anything making good use of multithreading.

Having had to go back and forth between a laptop and a desktop for a processor intensive application (AutoCAD) the difference was painful.

I have a >3 year old GPU that's still faster than any mobile GPU. I have been having 64 GB RAM in my desktop for ... 5 years now. Even in the summer my PC is completely quiet, even under heavy load. (Both the GPU and the CPU are water cooled with stock all-in-one coolers.)

Desktops are great.

This will be true for a long time - the design constraints are so totally different it would be foolish to use the same design in desktop and laptop systems.

The most limiting thing is TDP, which in the highest performance laptop processors is still capped at 45W, whereas a maxed out desktop processor can draw 100W or more.

See these tables for i9, for example, compare Coffee-Lake-S (Desktop) with Coffee-Lake-H (Laptop) https://en.wikipedia.org/wiki/List_of_Intel_Core_i9_processo...

My workstation has a 3990x in it. It may not be the fastest single threaded machine out there but there isn't a laptop available right now with 64 cores (128 with hyperthreading if that supports your workload). As a c++ developer, compilation speed is p0 to me and there isn't a laptop that comes even close.

The trend in laptops has been for longer battery life and less heat. Since there haven't been any major breakthroughs in battery technology or mobile processor power (at least from Intel), this means lower power for processors and generally lower performance in general. Almost all laptops are using ultra low voltage Intel chips. And even the ones that don't, except for high end gaming laptops, thermally throttle ALL the time.

As a result, your 10 year old desktop is probably 50-100% faster than the most expensive Macbook Pro or Thinkpad. It can be quite astonishing swapping to even an old desktop after using a laptop for a long time.

not only is it still true, there's never been evidence it's not been true or that it's going away.

Time after time, as someone who's been working on his 10 year old desktop (with a replacement ssd + graphics card when the old one died), I meet devs and analysts using laptops who reason more or less: "well it says i7 and it says x GHz and it says ddr3/4 and it's got a gpu with the same marketing number, so laptops perform the same as desktops cause they have the same hardware in them don't they".

Clearly, what they really mean is "I've never worked with and compared with a desktop". I suppose one of the problems is that SOME of them that have 'used desktops' were actually using neutered VMs in a shared corporate environment that run really poorly and are pretty underspec'd in a shared environment.

But every time, it's actually been the case that not only is the desktop faster and cheaper, but things usually remained faster on an X year old desktop hardware vs more modern laptops for any serious workload.

Edit: and in case it needs to be said, I have both desktops and multiple portable devices in my household because the downside of desktops is clearly portability.

Use a $3,000 gaming laptop. I guarantee it'll stutter and throttle and perfom less well than a same-gen $1,000 PC.

More expensive, less performant, and less serviceable with a suite of proprietary bloatware on top.

Yes. The same class desktop counter part (GPU/CPU) are generally faster than their laptop counter parts while remaining cheaper and more versatile

You answered your own question: CPUs are throttled down when there is too much heat. That happens all the time in a laptop. A desktop with enough air flow never has that problem (unless overclocked).

The amount of raw power you can drive will "always" be contingent upon your ability to dissipate heat. And the second law of thermodynamics being what it is, that ability is relative to the space you have (assuming you're using similar cooling technologies in both cases).

Laptops being power-conscious, they're usually much closer to the point of maximum efficiency on the power curve. In that sense you get better performance per watt. But that's negated by the increased front cost.

20/30% more is much faster (just check desktop/notebook results at https://www.cpubenchmark.net/ to name one)

AFAIK mobile CPUs max out at 8 physical cores, whereas you can get 16 at the higher end of mainstream in desktops, and up to 64 in the enthusiast segment. Core count isn't the whole story, obviously, but an important consideration for many applications.

Yes, they are. It was surprising to me how much faster a desktop was.

Yes. You only need to look at the power draw of mid to high end desktop CPUs to realize that’s not feasible to power or cool on a laptop.

Now heat and power consumption is the bottleneck of laptop performance. Performance laptops uses same CPU silicon to desktop (even different SKU, especially Intel) but their performance is limited.

I didn't see any specific numbers in reply to your comment, so I just want to point out that base clock Ghz for Intel and AMD is much higher for desktop CPUs than laptops. For your average click-read cycle, this feels better.

At full load, it depends on the heat dissipation; Dell's Precision 7XX0 dissipates heat well enough to keep the CPUs from throttling, but the 5XX0 does not.