Windows 10 Version 1607 (Anniversary update) - half memory being hardware reserved (Total RAM: 32GB but 16GB usable)

One of my Windows 10 machine which is running on DIY hardware (AMD platform) hit this issue.

The CPU is AMD FX6100 (6 Cores) 3.30GHz

Solution:

Upgrade to creator update (1703), the issue being resolved.

Windows 10 Version 1607 (Anniversary update) - half memory being hardware reserved (Total RAM: 32GB but 16GB usable)