This is one topic i'm not too well versed in. My brother up until now has had one Gtx 650. His MoBo has 3 PCI-e slots. This first will do 16x. If you plug in two Gpu's the first and second will do 8x. My question is, he got another Gtx 650 for Xmas, will the performance boost of two Gpu's in SLI make up for the slower PCI slot speed? How much in relative terms will the performance be bogged down? Is the performance loss enough to warrant getting another MoBo that can handle 2 16x Slots? Just trying to get a better understanding of how the performance would balance out. Thanks guys!