How cheap is cheap and what performance numbers are you looking for?
About as cheap as you can get:
For about $3,000 you can build a Supermicro OEM system with an 8-core Xeon E5 V3 and 4-port 10G Intel SFP+ NIC with 8G of RAM running VyOS. The pro is that BGP convergence time will be good (better than a 7200 VXR), and number of tables likely won't be a concern since RAM is cheap. The con is that you're not doing things in hardware, so you'll have higher latency, and your PPS will be lower.
What 8 core Xeon E5 v3 would that be? The 26xx's are hideously pricey, and for a router, you're probably better off with something like a Supermicro X10SRn fsvo "n" with a Xeon E5-1650v3. Board is typically around $300, 1650 is around $550, so total cost I'm guessing closer to $1500-$2000 that route. The edge you get there is the higher clock on the CPU. Only six cores and only 15M cache, but 3.5GHz. The E5-2643v3 is three times the cost for very similar performance specs. Costwise, E5 single socket is the way to go unless you *need* more. ... JG -- Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net "We call it the 'one bite at the apple' rule. Give me one chance [and] then I won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN) With 24 million small businesses in the US alone, that's way too many apples.