Synology 918+ Memory J3455

Preamble
Something doesn’t make sense with the J3455 and the memory configurations. What does it support?
Discussion
The synology NAS 918+ is reported to support only 8GB of memory, which ties in nicely with intel’s specification.
https://ark.intel.com/products/95594/Intel-Celeron-Processor-J3455-2M-Cache-up-to-2_3-GHz
There is talk that this is 8×2(channels) but I don’t really believe that at this moment as it has been reported some people have run 32GB on this NAS.
Investigating the hardware by examining /proc/cpuinfo
reveals:
address sizes : 39 bits physical, 48 bits virtual
Which seems to suggest that the cpu can address up to 512GB (39 bits) of memory.
As you can buy big DDR3 modules, the interface specification isn’t a restriction, and no-one would design a board to restrict the memory addressing without good reason.
So my feeling are that possibly the J3455 can address up to 512GB, has only been tested up to 8GB, in hardware QA test before shipping each chip. (Or even possibly CPU internally is only optimised for 8GB, but that I suspect is a longer shot.)
So dependent on how luck you are, your CPU may/may not work for a larger memory configuration. As they say you mileage may vary…

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