So, when I play Diablo II normally, the 4:3 stretches to fill the screen in the title screen and during gameplay of 800x600, or 640x480, during the splash screen of the logos when launching the game, and in the title screen. The cinematics also fill the screen except there are black bars on the top and bottom but I think that just might be normal behavior.

The reason I looked for a mod was because I have a Samsung KU7000 4K TV which is several years old, and it has a bug or quirk where if the TV's HDMI input label is set to PC mode when connected to a computer, some of the advanced settings in the picture settings are disabled and you cannot enable Game Mode either which disables unnecessary stuff and reduces latency. One of the advanced settings that is grayed out is the Color Space which is forced to be set to Native instead of Auto which makes the colors too saturated. If you manually set the TV's HDMI input to Console, however, you can get all the settings back and set Game Mode as well. Having Color Space set to Auto is a must for correct colors and following the D65 Color Standard.

The problem is that on old PC games which have low resolutions such as 640x480, or 800x600, the TV is forced to PC mode and those advanced picture settings are grayed out and even manually changing it to Console or any other mode doesn't fix it. Neither does messing with the Nvidia Control Panel.

The only way I was able to fix this was by using your mod. This enabled me to have the TV HDMI input mode be set to Console, have Game Mode enabled and have all the advanced picture settings enabled.

However, there are a few problems with your mod that I cannot figure out and I messed with the config file too, as well as Nvidia's settings, all to no avail:

1. If I set my resolution to the 640x480 or the 800x600 within the game's settings during gameplay, it forces the game into a 4:3 aspect ratio with big black bars on the left and right of the screen with no way to stretch it. Without the mod, AKA by playing the game normal, it is stretched to fill the entire screen.

2. If I set the resolution to 960x540, it now fills the entire screen, but only by zooming the game out further than it is intended by the normal game's resolutions. This makes the inventory and the information bar at the bottom a bit too long, and can introduce some artifacts such as seeing the far edges of the screen area sort of pop in as it loads. This can also make some enemies viewable before they should be.

3. The title screen is forced into 4:3 aspect ratio with the big black bars on the left and right of the screen and nothing can change it. No custom resolutions help either. The resolutions only activate during game play but NOT in the title screen or any cinematics, and the last part is the MOST important of the 4.

4. The cinematics are a little window now with NO way to stretch them to fill the screen. In the normal game, the cinematic is stretched to the left and right, but has black bars on the top and bottom. Since there are already black bars on the top and bottom, the mod, by forcing black bars on the left and right as well makes the entire video cinematic a little square/boxed window with black bars on both the left and right, and the top and bottom. This makes the mod almost unuseble for me as this ruins the immersion of the cinematics when they play.

I tried asking the Google AI (not Gemini) that appears at the top of Google search results and none of the tips are working, such as:

A. Enabling compatibility mode that forces the game to display in 640x480. This completely disabled the mod entirely and the forced PC mode with the locked advanced picture settings in the TV returns.

B. It says to set widescreen=false and fix_aspect=true in the config file. Neither of these are in the config file so I tried adding them myself, but neither of them do anything.

C. It says to add -nofixaspect after the -3dfx line in the shortcut of the game. This does nothing, and neither does adding it before the -3dfx line.

D. Changing the dxnowide and the noresmod settings doesn't fix it either.

E. Setting custom resolution in the Game section of the config file does not fix it.

F. It says to go into my Nvidia Control Panel and navigate to Display on the left hand panel, click on "Adjust size and position" and under the scaling tab, to select Full Screen rather than Aspect Ratio or No Scaling. Then it says to set Perform scaling to GPU rather than Display. And it says to check the box for "Override the scaling mode set by games and programs". This has literally NO effect whatsoever at all in any way, shape or form. That checkbox is supposed to FORCE all games and applications and programs to stretch the display to completely fill the screen whether it wants to or not, and yet it is NOT working! I tried setting it to Display as well instead of GPU and also tried with the box unchecked. None of the combinations will override the game's settings and force it to stretch.

So, what do I do to get the cinematics, the splash screen, AKA intro logo when starting the game, and the title screen to stretch to fill the entire screen? And how do I set the gameplay to stretch to fill the entire screen when selecting 800x600 or 640x480? This mod is the only way I know to unlock the other Picture Settings in my TV, yet I can't find a way to stretch the screen when in the lower resolutions during gameplay or when watching cinematics or the splash screen logos or during the title screen. NOT using the mod restores all of that, but then those picture settings in my TV are locked again.