I already have posted about my HP T520 thin client running Haiku elsewhere, but on a whim, I reduced the ram down to 2GB (from 4GB), & everything runs just as well as it did when originally installed.
Presently, 2GB ram, 16GB M2 SSD, dual 1.2GHz AMD processor, AMD graphics, using a USB wifi - (TP-LINK TL-WN822N).
“However, for a satisfactory user experience, we recommend at least a Pentium4 with 512 MiB of RAM and 3 GiB of storage space. For compiling Haiku within itself, we recommend using at least 2 GiB of RAM.”