Recently got a Dell Studio XPS Intel i7, X58 chipset, 3GB triple channel DDR3 RAM, Vista 64 with LR 64 and it seems to use the cores effectively. LR is a dream to use, sliders are smooth and responsive, local adjustments are a breeze. Best investment I've made in a while. The Dell isn't the highest performing i7 X58 system out there, others must really be impressive.