Passively cool an undervolted/underclocked i7 875k

It's been two nice years of using my i7 rig, but as the future demands higher performance, so do I. Working with nothing but video editing/rendering, a top of the line system is quite beneficial, so I plan on getting the latest and greatest from Intel in the near future.

That being said, I don't want to just cast my old setup aside, but I'l like to use it as a small little Minecraft/home server.

I would like to keep it absolutely silent, no fans whatsoever. As it is right now, doing that with any i7 would seem impossible. However, I plan on undervolting, underclocking, and disabling features on it.


What I plan on doing:

Underclock processor to ~1-1.8GHz, getting voltage as low as possible.
Disable hyperthreading
disable one or two of the cores

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The specs of this potential server:

Crippled i7 875k
Recycling my old p7p55d motherboard, probably
16GB RAM
120GB boot/data SSD
AMD Radeon 5450
A yet to be found passive powersupply


The primary thing this computer will be doing is running a Minecraft server. Chances are high that this will be done in a Linux server environment (such as this: http://minecraft.codeemo.com/ or just Ubuntu server) after I confirm stability in Windows 7.



Does this seem realistic? Could it be possible to have the i7 run passively by crippling it? Are there any specific heatsinks that I should consider using for this?