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0 pointsmschuster915mo ago0 comments

I've come across a few in the past, these 18 inch giant-ass "desktop replacement" / gamer things that had insanely large power bricks. Been a few years but I think they all had desktop GPU chips from NV.

But I think it's not possible to do any more, not with any high-power card that is... the RTX 5090 has a TDP of 600-ish watts, you can neither get in that kind of power into a laptop, even at 24 volt that's still 25 amps of current just for the GPU, and most importantly you can't get rid of 600 watts of heat, no matter what, without making the user uncomfortable.

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welferkj5mo ago

That's not the case. A 5060 has a 145W TDP, which is borderline feasible. A 5090 is 575W, which is approaching furnace territory.

mschuster91OP5mo ago

Thanks, fixed. I intended the 5090 indeed but haven't had a coffee.

Anyway, even the 145W of a 5060 are... an ugly challenge to meet. The 2019 16-inch MacBook Pro for example can happily guzzle 90W when you max out the i9 CPU and the dGPU and gets uncomfortably warm after a few minutes once the aluminium case goes into thermal equilibrium.

Add in even just a 60W CPU to match with a 5060 and you're looking at double that heat to be dissipated!

vladvasiliu5mo ago

Weren't those MacBooks relatively thin – the same as the OG retinas of 2012-2013?

A friend of mine has an Asus with some Nvidia GPU (3070? not sure), a 5th gen ryzen 9 and a 200+W power brick.

That thing is twice as thick as my 2013 MBP and the case is plastic. It also has more vents than my mbp, each of which has more surface area than all those on the mbp combined. I also suspect the fans are bigger.

He actually bought it to play games on it and never complained about performance dropping after a while. So I suppose it manages to move the 200 W of heat somehow.

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quickthrowman5mo ago

That’s still about two orders of magnitude less than an electric furnace (100A at 240V single-phase is 24kW)

Resistive heat is really crappy, a 7-8kW heat pump could replace the hypothetical 24kW furnace.

1Wh = 3.412141633 BTU/hr

vel0city5mo ago

The most extreme I've seen are some laptops that have two 240W power supplies, and even then that wouldn't be enough to reliably power these extreme high end desktop GPUs these days.

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