On the one hand, this is really cool. But, on the other hand, thats nearly $400 to use a $140 video card with a Macbook that's running Windows and basically behaving as a desktop computer.
It wouldn't be that much more expensive to just build a cheap Windows desktop with the same video card - especially when simplicity and low fuss are stated goals.
("Gaming computers" can be incredibly cheap. http://www.logicalincrements.com/ starts at $169, and the tier with a GTX 1050 Ti is $528. Also, given the 20% performance penalty from TB2, you could probably drop down a tier or two and still get the same result.)
Sure, but there are a few additional factors. First, $400 is the "lazy price". I had some credit card points to spend so I didn't want to waste too much time looking for deals. But if you wait for rebates, buy used, or get the less powerful non-Ti 1050, you could probably get close to $300. Second, I already had a very powerful CPU in my machine (as well as 16GB of RAM) and I didn't want to downgrade. Third, I move around constantly and prefer to keep my belongings to a bare minimum, so a compact eGPU box was far more compelling than even the smallest gaming PC case.
I've put a lot of thought and research into this already, and you basically summarized my thoughts on the matter. Building a gaming desktop is a better answer today.
But in a year, when you can buy a commodity Chinese-made TB3 enclosure for $200 that-- with a SINGLE CABLE-- powers your laptop, offers a bunch of extra USB3 ports, ethernet, audio jacks, and can also take a high-end GPU for gaming, well, that's a much more attractive proposition.
Along these lines, I was also curious about the quote
"the kind of CPU I could buy for cheap would be comically underpowered compared to the i7 4850HQ I already had in front of me"
Specifically: will the high-end i7 in a MBP run at Full Turbo indefinitely, or does it throttle down hard after a couple of minutes at full load to avoid overheating, like the one in my Dell Precision does?
I'm suspecting the latter, due to the basic physics of heat dissipation from a high-TDP chip. In this case, a sub-$200 Haswell i5 will run circles around it.
I've had throttling issues in the past (though mostly on the dGPU side of things). Dusting out the case stopped the problem immediately. I also imagine that heat will be far less of an issue with the dGPU sitting idle.
I had to make the same decision in June, and I built a Windows desktop instead of using an external GPU.
However, I hope that I won't have to do that again in the future. I'd rather have just one computer for the sake of simplicity. Hopefully external GPUs will become mainstream in a few years.
Yeah, a i5-6600k is a bit over $200 right now, and Ryzen is just around the corner. If a TB3 enclosure was, say, $100 (then you'd add an appropriate ATX PSU) and there were reliable, tested cables (and OSX drivers), I'd be all over this. EGPU has been around for a few years now and has yet to take off. Hopefully TB3 will remedy this, but I'm not holding my breath. I think a lot of the blame is on Intel, and hopefully with TB3 now they'll fully support eGPU.
It wouldn't be that much more expensive to just build a cheap Windows desktop with the same video card - especially when simplicity and low fuss are stated goals.
("Gaming computers" can be incredibly cheap. http://www.logicalincrements.com/ starts at $169, and the tier with a GTX 1050 Ti is $528. Also, given the 20% performance penalty from TB2, you could probably drop down a tier or two and still get the same result.)