Want to have your mobo cake now and eat the Thunderbolt later? Asus is there for you with its new Thunderbolt EX Upgrade card -- as long as you buy, or have bought, certain of its 7-series motherboards. The supported models have a "unique system link connector" to cable to the upgrade card, which will gobble up one of your PCIe x4 slots and use a DisplayPort to serve up the 'bolt. So if you don't feel like laying the cash down
