Ocean Technology LLC via Amazon offers the Unitek Uspeed 2-Port USB 3.1 PCI-E Card for $27.99. Coupon code "Y6YXYVY6" drops it to $12.99. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $8.) That's the lowest total price we could find by $49. It supports transfer rates up to 10Gb/s. Deal ends September 30.