Actually, now that you mention it, it could be 92mm. I only roughly measured and don't believe 95mm is a standard fan size. 92mm with 2500 RPM sounds like it should fit. But then again, you'll be looking at sinking even more money into an already expensive and not really ROI'ing device.
I don't know the place you are holding this Apollo device in your house, some different room or basement, and maybe you don't have problem with noise that is creating.For my devices I am always trying to reduce noise by doing some modification, but I am silence freak and I don't recommend this to anyone else.
If you are ok with setup you have now, don't cut or change anything
That only works if the SoC is efficient / produces limited amounts of heat. I don't think the Orange Pi 4 can be passively cooled like that; from what I can tell it is rated to 5V, 4A input, while the Raspberry is sold with a 3A power supply
I am not sure about Orange Pi, but I know that I can overclock Pi400 and it would still run cool and stable.It might be different story with Orange Pi especially if GPU is used for anything.
Interesting thing is that they are working on their new OS that is Arch-based Linux distribution, unlike Raspberry that is using modified Debian based linux OS.
Coreboot is a great addition to a trust-minimized node setup. It's questionable if that's needed for someone installing nodeJS 9 and a proprietary miner binary, though..
My point was that I can use those laptops for multiple use cases, for anything related with Bitcoin.