My system: XP2000+ not OC.
The pipes: 9mm internal diameter transparent plastic tube
The radiator: 11x12x20 cm (withxlengthxheight)
the home made block: aluminium 20 (or 25 not remember)mm thick, 60x80mm (withxlength) with 4 drilled holes, 2 connector (water in/out)
balance tank: a 1 liter plastic soft drink bottle. Will change to 0.2-0,05 liter.
About 0.7-1 liter water.
The bottom of the radiator is 30 cm over the CPU.
The case is open (need to drill two holes for the pipes, and I will close it)
fittings made by a lathe operator...
(pump: 220V 6W, 450l/h, for safety, never used...)
About zalman: some of my colleague played at snowball in the office... some snow->water on my graphics card... it's over...now I'm using TNT2 no fan no noise... no games...