Personally I would be more than willing to pay a premium for exceptionally quiet PC cooling, even if that meant having to use a case, CPU cooler, and GPU cooler all designed for each other.
They make passive CPU coolers that work fairly well on modern processors. Additionally, you can set fan curves on a GPU to only trigger in the case of a legitimate emergency (eg. 85c+, which you would never hit in casual non-gaming workloads), which would probably get you 90% of the way there.
