You have a few things to consider. Firstly, three GTX 480s are going to draw a lot of power, so you're going to need a beefy power supply and you also need to consider that your utility bill will go up. Then you have to look at your motherboard and make sure that you have 3 PCIe x16 slots AND that your motherboard supports SLI. If it's a budget board, then I doubt it.