you would be surprised at much weight a motherboard can hold,
and you would also be surprised how much weight a cheap motherboard cannot hold.
I switched to AIO back in 2010 I believe, the old first gen corsair H50 is still being used daily in an X58 | i7-920
My current X99 is using an H110 vanilla type AIO (No RGB/iCue garbage) since 2015. and people are amazed that my temps are so low.
Setting at 75.5F Ambient with 30C CPU IDLE temp.
As for Air Coolers, I used a lot of the old Zalman Solid copper CNPS/9900/9700/9500/etc cpu coolers in many builds.
One build in particular I remember it was shaped like a Taco I think it was a G41 or G31 Foxconn board. the PCB was so thin. Even the stock cooler tacoed it.
Not due to weight, but installation pressure.
As for the enthusiast boards there were never any signs of tacoing or warping from these large Solid Copper coolers.
The most recent air cooler I used was a Cooler Master - Hyper 212 RGB Black Edition.
With an ASRock Z390 Phantom Gaming 4. The board looked very thin, So I put it in a Server Chasis to lay flat like mentioned by "HeavyHemi"
However this barley fits, as the top pipe ends touch the lid of the 4U Server Case. just barely, but not a problem.
And you can see in the photo the cable management is for crap.
Your choice on the Corsair 1000D is an awesome case as I myself have contemplated getting one, but Hard Drive support is almost non existent which is why I love the 760T
However, Like You, I always like the idea of air coolers for the reliability if the mechanics fail it still passively does the job.
But I've had no failures on my AIO builds, but had some fans start rattling and vibrating, and were replaced by 5 years warranty coverage.
I think the EVGA Enthusiast boards should hold the coolers, but I have not any these giant new cheap aluminum coolers.
1500 grams is twice what they used to be. I would not use one personally this size is ridiculous.
Why everyone is going to aluminum to make it cheap, and still charging like it's copper has me boggled. money greed I reckon.
Even the liquid cooling is all plastic and aluminum these days.
Copper For The Win.
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