Windom shaders are a great choice for weak PCs, because with them Minecraft will be much more beautiful, while keping acceptable FPS rate. With them you can add beautiful shadows, light blur in motion and other realistic effects. Many options can be configured at will or just turned off.
How to install Windom shaders
Make sure you have Optifine installed and working correctly.
Download the shaders and leave it archived.
Launch Minecraft, then go to Video Settings.
In the ‘Shaders’ section, select ‘Shaders Folder’. The ‘shaderpacks’ folder will open, copy the shaders file there.
After copying, the shader will appear in the list. Click it to choose.
Start a new game or load an old one. Shaders will work in all saves.