Those Eurocom laptops look neat, thanks for the tip.
I'm just a bit surprised if they manage to squeeze out significantly better thermal performance than Dell does out of a similarly bulky laptop.
Have you actually verified the core frequencies over time with a tool like CPU-z when running a workload that pegs all cores at 100%?
The Precision model I have doesn't stutter or feel any slower under load. I've never managed to make it feel slow, even when running heavy physics simulation codes on all cores in the background. But when you actually monitor frequencies, you see it clocks down by around 20%.
Right, let's clarify what I mean by "throttling". All intel CPUs have base and turbo speeds, and the turbo speeds usually only apply to a single core or to multiple while there is thermal headroom. By "throttling" I do mean the CPU falling below its base frequency to protect itself, I don't mean the turbo frequency falling down under load, that's normal and happens even on desktop CPUs with ample cooling.
As an example - the CPU in the Razer Blade is an i7-8565U, with base speed 1.8GHz, turbo speed 4.6GHz. Under maximum load I'll see it jump to 4.6GHz briefly, and then settle at 3.2GHz where it will remain indefinitely. Sure, the CPU has "throttled" down from its maximum turbo speed, but it's stable at 3.2GHz on default cooling. In comparison, I used to own an MSI GT63R with a quad core i7(2630QM if I remember correctly) and that CPU would "throttle" by regularly falling down to 400-600MHz(!!!) as a result of stretched thermals. It was not "stable" at neither its base nor turbo speeds. That behaviour still happens(in the mentioned Air, or an XPS 15 for instance) but there are definitely laptops which don't do that at all.
Ah, okay, then I'm using a different definition of throttling.
Intel will publish as you say a base speed of 1.8 GHz, then a single core Turbo speed of 4.6 GHz and also an all-core Turbo speed of 4.2 GHz (numbers made up, but something like this). If sufficient cooling is available, the CPU should be able to sustain the all-core Turbo number indefinitely. If it can't, I call that throttling. It can be mild (if you go from 4.2 to 3.2) or severe (if you go from 4.2 to 1.8). A colleague has the XPS 15 (well, the Precision equivalent) and he's never seen it drop below base clock, the problem with it is that base is something ridiculously low like 1.2 GHz. If a machine drops below base freq. due to thermal issues, it has been designed ver wrongly.
Our workstations with water cooling run at maximum all-core Turbo freq. for days on end. Those CPUs do exceed the specified TDP when doing so, which is fine as long as the cooler can easily dissipate that heat. And you can get water coolers that support 500W TDP, so no worries.
The only guarantee Intel makes is that the processor will stay within TDP when running at the base clock. What's happening when your laptop goes briefly to 4.2 GHz is that it exceeds both the Intel-stated TDP and the cooling system TDP. Then it throttles back to 3.2 GHz, which is a little below the cooling system TDP but above the processor TDP. In a laptop like the XPS 15, the cooling system TDP is only a little higher than Intel-stated TDP.
The momentary thermal headroom between what the CPU puts out at max Turbo and the cooling system TDP is provided by the heat capacity of the metal in the heatsink/heatpipe.
I'm just a bit surprised if they manage to squeeze out significantly better thermal performance than Dell does out of a similarly bulky laptop.
Have you actually verified the core frequencies over time with a tool like CPU-z when running a workload that pegs all cores at 100%?
The Precision model I have doesn't stutter or feel any slower under load. I've never managed to make it feel slow, even when running heavy physics simulation codes on all cores in the background. But when you actually monitor frequencies, you see it clocks down by around 20%.