Intel EXPI9301CT Gigabit CT PCI-Express x1 Desktop Adapter for $22.99 shipped after coupon code EMCNGNB33. Here is a screenshot for your reference. Note that this is for PCI-express expansion slot. This network adapter goes up to 1000mbps. One advantage of using this particular network card is that it allows the computer’s main CPU to off load almost all network related activities to it so the main CPU is freed up to perform other tasks. Most other network cards typically still rely on the main CPU to take care of most network tasks. Most places have this Intel Gigabit Adapter for about $31.