Here is a shortlist of things that have affected the game since launch you can check for to see if they help:
- intel direct storage (dstorage.dll file in the Diablo IV installation directory) rename or delete it.
- Crossplay (for both play and communication) disable them.
- Logitech keyboard/mouse software - try removing or shutting down.
- Razer keyboard/mouse/headphone software - same.
- Peripheral Lighting (ChromaEffects) disable this in the game, or by using the method described above.
- GPU Scheduling - This is enabled in Windows.
- nVidia Experience - Specifically regarding the use of gaming profiles. May need to reset/clear the profile, or potentially do a driver install using the clean install check mark option.
- Windows Graphic Settings - There are specific graphic settings in Windows for games. Same section as the GPU Scheduling. Use High Performance (Your Video card Model)
- CPU/GPU overclocking - Essentially making sure your CPU/GPU are not overclocked or are running at proper defaults. This affects primarily 13th and 14th gen CPUs.
- CPU Affinity - You can set the Affinity of the game to a specific core (or cores) of the CPU. This is done via the task manager under details by right-clicking the EXE of the game while it is running. It has to be done manually each time its launched.
- Swap File Size - This refers to swap memory settings. Setting the swap file to a custom size can help the system performance and prevent out-of-memory issues. Minimum suggested setting is 16GB (16384MB) for minimum and maximum size (set both to the same value).
- Previous or earlier driver - Essentially either revert or remove and install an older version of the card driver. Instructions and driver removal tool can be found here :
https://www.guru3d.com/download/display-driver-uninstaller-download/
- Ray Tracing - Disable RT for now in your game.
- Scan/Repair - Do a scan and repair of your game installation.
- SSD - Make sure you are running the game from an SSD only.
- Network - This game can be problematic on some WiFi network system cards. Whenever possible always try to play from a hardwire connection. Wireless networking can muck up connection reliability and cause ping spikes, drops, or other problems.
- Compatibility Mode - This happens occasionally. You open the installation folder, right click-properties the game EXE file, and make sure its not set to run in compatibility mode. Same for the Battlenet Launcher.
- Clean installation - This game uses a custom CASC file system (within its data files). As the game is patched and updated, this system can fragment. Occasionally its a good idea to fully delete the game folder and re-install the game to fix that fragmentation.
- Interfering programs - You may need to review running programs that are active at the same time as the game. One could be causing some issues simply by running while playing. You can eliminate programs by shutting them down and running the game while they are not in use.
I will add some other suggestions as I remember them. There were a LOT of small things that could fix a lot of the same problems.