In-game stutter(looking for clarification)

Would appreciate a reply, helpful or otherwise.

Like for certain other people, since patch 8.1.5, the WoW experience turned into a real stutter-fest, 2 minutes loading screens, 2-3 minutes for character to appear, etc.
Suffice to say, i’ve tolerated it and periodically looked for causes and solutions.

After reading an older forum post from a person who had the same issue, i narrowed the culprit down to it being the RAM and after googling for a period of time in more detail, i came to something known as DDR3 and DDR4, to my understanding the types/sockets where the RAM is, or something like that, since my hardware knowledge is that of a blank paper.

Followed by CPU compatibility with the RAM in regards to somewhat modern hardware, i suppose.
Now i do have DDR3 and i was beginning to wonder if that could be the cause if the atrocious stuttering in game in places that involves 1+ players appearing, or large texture loading.

Ill leave my PC specs below, and perhaps someone can clarify if that is the case and since the ‘‘better’’ DDR4s cannot be used in DDR3 sockets, would that means literally replacing my whole motherboard and RAM to be able to reasonably play WoW.

CPU - i5-4460 3.20 GHz
RAM 8 GB, DDR3
Hard Drive - SSD
GPU - Nvidia GeForce GTX 750Ti 2gb

The CPU usage is typically around 50-60% during game time, 60-70% for RAM and 50%+ for GPU.
Mind you, before 8.1.5 the game play, by my standards, was pitch smooth, no stutter, no lag, nothing.

Thanks in advance.