The mounts appear to be quite narrow, but a colleague managed to fit a pair of TX3 coolers with the use of a dremel to grind out a couple of notches to get it to fit.
I've now replaced all the fans and it's much quieter, and really don't think cooling is too much of an issue, but think I would rather move the HDDs inside the case, as I think that's the 2nd biggest cause of noise.
Motherboard is an X8DA6
http://www.supermicro.com/products/m...5500/X8DA6.cfm
Good point about the coolers and M3 rather than M4 screws - I think that's what actually tripped up my colleague.
We used to have piles of massive coolermaster cases around our office (as that's what we migrated all the old machines into (so we could recycle the chassis for newer hardware)
I wouldn't mind finding a decent size case in the UK, and a more efficient PSU - but we are just so limited for choice down here in Aus.