dont bother with gtx465 in sli, you need at least a 750w good brand PSU, and serious cooling. those cards run notoriously hot and suck power. If you do want to do this, you will need to spend another $150 on a motherboard.... I say just put that money towards a better single graphics card and you will have something newer and more efficient and just as powerful. You can then sell your old card for some more $$$ too.