Something doesn't add up here. As someone who has only recently built a home-server from an E5-26xx v2 on DDR3 RAM (because I have a sh*tload of 32g DDR3 DIMMs), I can confidently say that the newer cores (E5-26xx v3 and v4) only run on DDR4 memory...
So either you have a v2 instead of a v4 (and run on DDR3 memory), or you have a v4 but with DDR4 memory (not DDR3)
So either you have a v2 instead of a v4 (and run on DDR3 memory), or you have a v4 but with DDR4 memory (not DDR3)
Everything else doesn't work