So my 4-year old Intel NUC 5I5MYHE which I have been using as an ESXi server finally decided to give up the ghost. While on the lookout for a replacement, I came across William Lam’s excellent post at https://www.virtuallyghetto.com/2019/03/64gb-memory-on-the-intel-nucs.html where he tested 2x 32GB SODIMMs on his Hades Canyon NUC (supported), and found that it was also possible to run 64GB of RAM on his older 6th Gen NUC (not technically supported). He speculated that later generations of NUCs would be capable of running 64GB RAM too.
After a bit more research, I wound up choosing the NUC 8i5BEH because it had 4 physical cores, and with hyper-threading could present up to 8 vCPUs on ESXi. God knows I’ve been needing at least 6 vCPUs for the longest time to run some lab VMs. The only unknown was whether the NUC 8i5 would support the Samsung DDR4 32GB DIMMs (P/N M471A4G43MB1), and whether it could finally support 2x 32GB for 64GB RAM. More RAM is always a good thing, right?
I bought the NUC locally in Singapore, but had to get the RAM module from Amazon US. It simply wasn’t available anywhere else here. Finally, when everything arrived, it was time to unbox and start assembling.
Assembly done, I tried booting up the NUC and immediately ran into issues. I didn’t manage to capture a screenshot, but booting ESXi 6.7u1 would always fail when it was loading some drivers. With nothing left to lose, I thought a BIOS upgrade might help. I downloaded version 0066 for NUC8i5, and proceeded to run the upgrade.
After that, ESXi booted up without issues, and went straight to work with 32GB RAM installed. No fuss!
In any case, the first gamble of using the 32GB DIMM paid off. I immediately ordered another 32GB DIMM off Amazon, which took an agonizing 9 days to arrive. It was somewhat my fault, I wasn’t around for the first few delivery attempts.
So, the moment of truth: Does the Intel NUC8i5BEH support 64GB of RAM? Happily, the answer was “Yes”.
I’ve been running this for a few days with multiple VMs powered on, and this baby has been rock solid so far. Definitely a very viable home lab solution!