Thermaltake's Water 2.0, but I replaced the rad with a BlackIce unit I got from TNT2bluz a couple of years back.
4.5 is super easy for this chip, didn't even have to raise voltage. Gonna try taking it to 5.0 on the weekend, but first things first, when this stability test finishes it's time figure out SVID and offset voltage so I can get a proper 24/7 setup that doesn't compromise on idle power.