eBay

For sale is a working Intel Xeon E5-1680 v2 unlocked 8-core/16-thread Ivy Bridge-EP CPU for LGA 2011.

This appears to be a great chip for overclocking, as it will do 4.3 GHz at just 1.12v vcore completely stable. That's the speed and voltage I've been running it at since the day I got it, and even my OG Cooler Master 212 Evo could handle it!

I will now include a bonus Core i5-3330S processor. Tested to be working just fine, this is an Ivy Bridge low-power ("S") quad-core CPU for LGA 1155, running at 2.7/3.2 base/turbo. 6MB of L3 cache.