I've unchecked the 'max memory usage' setting, with minor results (i.e. Yes, I'm on a 64-bit Windows operating system. It's clear that this isn't Windows itself reserving memory for core processes, but rather something else allocating stupidly high amounts of memory inappropriately for itself. Has about 3.38GB of its 7.88GB total memory flagged as 'available'. After noticing some performance issues even running one tab on Chrome (Roll20, a graphically-intensive website) with absolutely nothing else, I did some digging.
Brief summary: I have an ASUS laptop with 8GB of RAM installed.