this is crazy...
what you want to get rid off, is what I let blow under my table currently

probably almost the same temperature streaming from an old Siemens P4/3Ghz that houses my Scope cards
(it was dead cheap, takes full size cards and is top quality)
got only one fan for PSU and CPU combined and emits it's load not to the back, but to the side.
as the central heating automatically regulates itself down at night, this is a great convenience.
(my room facing north east, great old building but not much insulated)
cheers, Tom