LGA2011 was an especially cursed era of processors and motherboards.

In addition to all of the slightly different sockets there was ddr3, ddr3 low voltage, the server/ecc counterparts, and then ddr4 came out but it was so expensive (almost more expensive than 4/5 is now compared to what it should be) that there were goofy boards that had DDR3 & DDR4 slots.

By the way it is _never_ worth attempting to use or upgrade anything from this era. Throw it in the fucking dumpster (at the e waste recycling center). The onboard sata controllers are rife with data corruption bugs and the caps from around then have a terrible reputation. Anything that has made it this long without popping is most likely to have done so from sitting around powered off. They will also silently drop PCI-E lanes even at standard BCLK under certain utilization patterns that cause too much of a vdrop.

This is part of why Intel went damn-near scorched earth on the motherboard partners that released boards which broke the contractual agreement and allowed you to increase the multipliers on non-K processors. The lack of validation under these conditions contributed to the aformentioned issues.