So, if you are having performance issues and you are on an older system, you may need to update your audio drivers. I tried everything, Underclocking my GPU to prevent overheating, System scans for malware, Disabling hardware acceleration in the Blizzard launcher. Setting my PC power limit to 99 percent as opposed to 100. Disabling crossplay. Running on the lowest gfx settings, Checking every process in the task manager that I wasnt sure about. The thing that seemed to work, at least it feels like it did as I have played the game without stutter and severe slow down in towns and dungeons for hours now. Normally it would take 20 to 25 minutes for the performance to deteriorate to an unplayable state. I just installed the manufacturers recommended audio drivers and it stopped with the memory leak type behaviour. Before, I had stutter to the point that my PC needed a restart. Diablo 4 is actually enjoyable again. I almost gave up on the game. Thought it was time to get a new pc.
for me closing the game and starting it up again fixed any ram overload. but yeah running a 4090 and having the stutters and 1 second responds time for click to action. luckily i run the game for 1½-2 hours before any sign of stutter appear.
After a windows update, the game went from smooth to hell.
I did a lot of cleaning, cleanly installed drivers (safemode, DDU method), cache cleaning and made sure my nvidia settings and game settings was as it should, and nothing fixed it.
I ran msinfo32, and saw that my pagefile.sys, was located on my worst drive. I changed that to my fastest ssd drive, and it solved it. You have to actually see in msinfo32 after the reboot that it actually changed, and make sure you set your slow drive in the settings to “none”.
I suspect maybe windows at some point changed it to my slowest, and it just went alphabetically. That if there was too little space on C:, it went to D: (which was my slowest).
Use chatgpt for the details on how to change your pagefile.sys location.