Hi Guys!
It's been a bit since I've been in here so sorry for the delay!
rrjwilson - I upgraded to a quad core whilst at uni. I was doing a 3D project and couldn't wait 30seconds more for my test renders

Anyhow, once that project was complete I saw no benefit of the quads (money locked up tbh). My biggest concern of downgrading was the degraded performance in Supreme Commander - to my surprise hardly any noticeable difference (imo, playing single play skirmish battles with 1k unit limits).
I still do a bit of 3D rendering and the difference is obvious between the dual and quad.
The heatsink does have a fan - the fan from my Thermaltake Big Typhoon. routing of air is a bit more complicated and needs some photos to explain whats going on (I'll do that tomorrow).
The cpu is currently clocked @ 3.8GHz with the following temps:
Idle: 44c (average core temp)
Load: 55c (average core temp)
Room temp: Roughly 26/28c

- please bear this in mind!
Ram: 5-5-5-18 @ 1:1 (system fsb 430MHz)
System is okay for the only game I play at the moment lol
Team Fortress 2 (minimum 35fps | 1680x1050)