TigerDirect offers a 2-Port USB 3.0 PCI-Express Interface Card together with the Seagate FreeAgent GoFlex Desk Desktop Adapter, model no. STAE107, for 97 cents. With $6.29 for shipping, that’s the lowest total price we could find for any USB 3.0 PCI express card alone by $6. (It’s also a price-low for this bundle by $51.) This card adds two USB 3.0 ports to any desktop with an open PCI express slot. The GoFlex Adapter is designed to make any Seagate GoFlex Desk external hard drive compatible with USB 3.0.