Low FPS

Windows and your PC

1. Use the right graphics card. On a laptop with two GPUs, Windows often runs games on the weak built-in one. Open Windows Settings, System, Display, Graphics, add Sour Client's Java (the javaw.exe under %USERPROFILE%\SourClientData\runtimes) and set it to High performance.
2. Plug the laptop in and set Windows' power mode to Best performance. On battery, most laptops cut the GPU's speed hard.
3. Update your graphics drivers from NVIDIA, AMD or Intel.
4. Close heavy background apps: browsers with many tabs, recording software you are not using, game launchers downloading updates.

In Sour Client

1. Set FPS Performance Mode to Balanced or Extreme (what each does).
2. Keep the performance pack switched on. Sodium, Lithium, ImmediatelyFast and More Culling do most of the work.
3. In crowded lobbies, Entity Render Distance stops drawing distant entities; its occlusion culling is on by default here.
4. Lower Particles, and turn off Motion Blur and menu blur if you do not need them.
5. Check the HUD: dozens of widgets on Quality mode redraw 240 times a second. HUD Refresh Rate can lower that.

Minecraft's own settings

• Render distance and Simulation distance: lower both. 8 to 12 chunks suits servers.
• Video Settings (Sodium's tabbed screen): Graphics Fast, Clouds off, and leave Sodium's performance options on.
• Shaders (Iris) cost more than everything else combined. Turn the pack off to test.
• RenderScale (in the pack) can draw the world at a lower resolution while the HUD stays sharp.

Memory

Set the profile's memory to 4 to 6 GB. More is not faster: past what the game needs, it only makes memory clean-ups longer.