Not a good call. The benefit to the H50 is being able to draw air in from outside the case. After that, it's got just the same surface area as anything else, and has to get rid of the heat from a pump as well. It'll do worse.
I'm running
this passively on an e8400, after taking the fan off. Temperatures hit 70 under heavy load, which it rarely sees.
If you want a silent computer I fear you're going about it the wrong way. Start with quiet components, then quiet cooling, then start to obsess over sound dampening and so forth. The biggest issue you're likely to hit is either:
1/ You want fast and silent, but cheaply, or
2/ The psu is now the loudest thing in the system