I recently purchased a NUC8i7BEH. Till now I am very content. Except for the fan noise. Since I tweaked the cooling settings it is already better. But it is not as quiet as expected.
I only installed a M.2 SSD (970 PRO 1TB). So Iwonder: would the air flow and cooling improve if I remove the SATA drive bay? Because I don't need it. Is it possible at all?
No, it won't improve cooling. it will actually make it worse! The drive bay is used to help with the cooling of the M.2 SSD drive, so removing it is a bad thing.
Really, what you want to do is play with the settings in Visual BIOS. The presets are all awful as far as I am concerned. I use my own set:
Give these a try and see if they help. If they aren't quite good enough, you can adjust the Minimum Temperature for the Processor as high as 75 without changing any of the other parameter settings. I don't recommend going any further than that - and, in fact, recommend staying at or below 70 if you can help it.
Hope this helps,