Windows not handling RAM properly?

[KaiserRandall]

I have 24gb of ram, and at idle my system uses about 11% of that. I use Firefox as my main browser and given I have a few maybe, 4 tabs at most open, Facebook, Twitch, Youtube, and maybe another google search I forgot to close, at most using about 4,000mb. Now, I also usually have all this open when I go to play Cities Skylines, which, at launch and first opening a map, its own RAM usage jumps to about 14,000mb, or about ~70-80% total RAM of my PC filled (according to task manager). This 14K mb does not stay this high however, after about an hour of play, it drops to something manageable like 2-4000mb.

 

Now this where it gets to my problem, and I should say it now: I have never ONCE got a message saying "You are low on RAM" or anything of the sort, but after awhile, programs start to act odd, namely Firefox, my Nvidia driver, and Cities itself. Some of the problems I'll list here I don't always get, and they are never in any specific order/severity, but only happen when Cities Skylines is running and has had its RAM usage at some point be around ~14,0000mb:

 

- I will get random Firefox errors, such as Firefox itself telling me a tab has died, and I have to refresh the page

- If its a YouTube video, it will go to the static screen (in the player) telling me an error has occurred and I have to refresh the page to get it to continue to work

- If its a twitch stream I will get a black screen in the player and it will tell me an error has occurred and I have to refresh the page to get it to continue to work

- Sometimes these above issues happen all at once, or only 2 out of 3, or any combination, but if its usually more then 2 or so of these at a time, its enough time for me to say "Uh oh", and hit ESC in Cities to bring up the menu to save, only to then have a perfectly normally functioning Cities pop a crash message and then close

- If its just one of these errors, more then likely I just need to refresh the tab and I can continue to play Cities regardless

- Sometimes after hitting the "OK" button on the Cities crash pop message this will prompt my Nvidia Display drivers (up to date) to crash (GTX 1080 btw), resulting in a black screen on all 3 of my monitors, sometimes not coming back on and requiring a full system reset

- Sometimes I will have none of these issues and Cities will give me the same crash pop message when I go to save my work and the same occasional Display Driver crash will occur after I hit "OK" on it. 

 

My hypothesis is either:

that Windows is not allocating RAM correctly after a program has used a significant amount, and is now no longer using that RAM space, is allowing programs to use that RAM space as their own, they are then unable to because Cities is using it still (despite windows reporting that it might not be), causing the program (Like the Display Driver or Firefox) to then experience errors.

OR

Cities is STILL using that RAM space, not reporting that correctly to windows, and when other programs (like the Display Driver or Firefox) try to access it, there is an error.

 

I have no way to isolate this issue as I do not have any other means to load up my RAM, and then have it slightly diminish its usage over time and see what effect this has on other programs on my PC.

I should also note again that NONE of these issues in Firefox, or my display drivers happen unless Cities is running and that it has used an extensive amount of RAM.

 

My question to you guys is that is this a Windows problem? Cities Skylines problem? Or possibly hardware? (its 3x8gb GDDR3 sticks for 24gb total) Is there anyway to purposely assign RAM space to Cities that ONLY Cities can access to mitigate this issue?