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)
Everything else doesn't work
This is not true. A few well known brands made both DDR3 and DDR4 servers that support v3 & v4 chips. Ask me how I know :-)
It looks like Supermicro had some DDR3 Xeon v3/v4 boards, and the first thing that came to mind was a Shenzen workstation/gaming board using recycled parts... haven't searched on that but it's bound to exist.
Yeah, the Intel reference page only lists DDR4, not DDR3:
https://www.intel.com/content/www/us/en/products/sku/92986/i...
> 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)
Yup that's odd... I've got a Xeon 2680 v4 (14 cores) (amazing bargain of a little beast btw) and it's indeed on DDR4 and I saw all Xeons v4 as supporting DDR4 only.
Full spec (brand/model/mobo type) would have been nice: mine's an HP Z440 workstation repurposed as a server (which I only turn on when I'm working and which I religiously turn off before going to bed).
There are some OEM-only v3/v4 parts with dual memory controllers (because of a RAM supply crunch at the time, funnily enough), but the E5-2620 v4 is not one of them. The classic example is the very popular 12-core E5-2678 v3.