More FPS on an older PC

Rust is heavy. An older GPU can still run it well if you turn off the expensive stuff. Do section 1 first. It is most of the gain. Sections 2 and 3 squeeze out the rest. Low ping but choppy frames? This page is for you. Rubber-banding with good FPS is a route problem: type /lag in game instead.

1. In-game settings (Options, Graphics)

These are the sliders in the menu. Under each one is the console command that does the same thing, if you would rather press F1 and type it. Change them in this order. Restart the game after changing textures.

Draw Distance 1000 to 1500graphics.drawdistance 1200: How far the game renders terrain and objects. The single largest cost on any card. Bases and players still load at any value; only far scenery fades. Below 800 looks bad and can hide roof campers. 1200 is the sweet spot.
Graphics Quality 0 to 2Menu only, no convar: A master preset that sets many of the settings below at once. Set it low first, then adjust the individual ones.
Shadow Quality Lowestgraphics.shadowmode 1graphics.shadowlights 1: Dynamic shadows are a whole second render of the world from the sun. Mode 1 is hard shadows, the cheapest. Modes 2 to 4 are softer and cost more. Max Shadow Lights is how many lamps and fires can cast shadows at once; 1 is the minimum, the game will not accept 0. There is no true off. Lowest has no PvP downside.
Anti-Aliasing Offeffects.antialiasing 0: Smooths jagged edges. Costs frames on every pixel. Turn it off, or use FSR / DLSS below instead, which does the same job cheaper.
Upscaling: DLSS or Render Scale DLSS Performance, or 0.8graphics.renderscale 0.8: The game renders at a lower resolution and scales it up. This is how a weak card fakes a stronger one. DLSS needs an RTX card and is in the menu. On any other card, Render Scale does the same job: 0.8 renders at 80% and looks nearly the same. Go to 0.7 if you need more. Below 0.7 gets blurry.
Motion Blur, Ambient Occlusion, Sun Shafts, Lens Dirt, Bloom, Depth of Field Offeffects.motionblur falseeffects.ao falseeffects.shafts falseeffects.lensdirt falseeffects.bloom falsegraphics.dof false: Post-processing effects. Each one is a pass over the whole screen. None of them help you see players. Motion blur actively hurts you in fights.
Water Quality 0 and Water Reflections Offwater.quality 0water.reflections 0: Reflections render the world twice near water. Off on the coast is a big win.
Terrain Quality 0terrain.quality 0: Ground detail and blending. Low is fine; you are looking at players, not dirt.
Grass Quality 0 and Grass Displacement Offgrass.quality 0grass.displacement false: Grass density and grass that bends when you walk through it. Off is also a real PvP edge: nothing to hide in.
Texture Quality Medium, or Low under 4 GB VRAMMenu only, no convar: How sharp surfaces are. Textures live in GPU memory, not GPU speed. If your card has enough VRAM, Low does not add frames; it only adds pop-in. If it has 2 or 3 GB, Low stops the stutter from swapping.
Anisotropic Filtering 1graphics.af 1: Keeps textures sharp at a shallow angle. Small cost, no PvP value. Lowest setting.
Vsync Offgraphics.vsync 0: Locks frames to your monitor. Adds input lag and can halve your FPS when you dip below the refresh rate. Off.
FPS Limit 0 or your refresh ratefps.limit 0: 0 means no cap. Cap it at your monitor refresh rate if the card gets loud or hot.

2. F1 console convars

A convar is a console variable: the text version of a menu setting. Every line here matches a setting in the menu. Press F1 in game, paste the whole block into the console, press Enter. They save between sessions.

graphics.drawdistance 1200
graphics.shadowmode 1
graphics.shadowlights 1
graphics.parallax 0
graphics.af 1
graphics.contactshadows false
graphics.dof false
graphics.renderscale 0.8
effects.antialiasing 0
effects.ao false
effects.motionblur false
effects.shafts false
effects.lensdirt false
effects.bloom false
grass.quality 0
grass.displacement false
terrain.quality 0
water.quality 0
water.reflections 0
mesh.quality 0
particle.quality 0
decor.quality 0
tree.quality 0
fps.limit 0
graphics.vsync 0

What each one does.

Draw distancegraphics.drawdistance 1200: Same as the menu slider. 1000 to 1500.
Shadow modegraphics.shadowmode 1: Shadow quality. 1 = hard, 2 = soft, 3 = high, 4 = very high. 1 is the cheapest. The game default is 2.
Max shadow lightsgraphics.shadowlights 1: How many torches, lamps and campfires can cast real-time shadows at the same time. Each one is another shadow render. 1 is the minimum the game allows.
Parallaxgraphics.parallax 0: Fake depth on the terrain surface. 0 = off, 1 = offset, 2 = occlusion. Off.
Anisotropic filteringgraphics.af 1: Same as the menu. 1 to 16; 1 is disabled.
Contact shadowsgraphics.contactshadows false: Tiny extra shadows where objects touch the ground. Off.
Depth of fieldgraphics.dof false: Blurs the background when you aim. Off.
Render scalegraphics.renderscale 0.8: Renders the world at a fraction of your screen resolution and scales it up. 1 is full size. 0.8 is a big saving that still looks sharp. The UI stays full size. The cheap alternative to DLSS on cards that do not have it.
Anti-aliasingeffects.antialiasing 0: Same as the menu. 0 is off.
Ambient occlusioneffects.ao false: Soft shading in corners. Off.
Motion blureffects.motionblur false: Off. Hurts aim.
Sun shaftseffects.shafts false: Light rays through trees. Off.
Lens dirteffects.lensdirt false: Smudges on the screen when facing the sun. Off.
Bloomeffects.bloom false: Glow around bright things. Off.
Grass qualitygrass.quality 0: Same as the menu. 0 to 100; 0 draws no grass.
Grass displacementgrass.displacement false: Grass bending when you walk. Off.
Terrain qualityterrain.quality 0: Same as the menu. 0 to 100; the default is 100.
Waterwater.quality 0 water.reflections 0: Same as the menu. Reflections: 0 = off, 1 = simple, 2 = full planar (renders the world twice).
Mesh qualitymesh.quality 0: Detail of world models. 0 to 100.
Particle qualityparticle.quality 0: Smoke, fire, explosions, dust. 0 to 100; 0 keeps them but simpler.
Decor qualitydecor.quality 0: Small rocks, bushes and clutter on the ground. 0 to 100; 0 draws the fewest.
Tree qualitytree.quality 0: Tree model detail. 0 to 100.
FPS limitfps.limit 0: 0 is uncapped. Use your refresh rate to cap. The game clamps it to 240.
Vsyncgraphics.vsync 0: Same as the menu. 0 = off. 1 waits one screen refresh per frame, 2 waits two.

A line says "unknown command"? Facepunch renames convars sometimes. Type the first part, for example effects., and press Tab. The console lists the real names. Skip any line that does not exist.

3. Steam launch options

In Steam, right-click Rust, Properties, Launch Options. Paste this line.

-high -force-feature-level-11-0 -window-mode exclusive -nolog

-high: Runs Rust at high CPU priority so Windows gives it the cores before Discord and Chrome.
-force-feature-level-11-0: Forces the DirectX 11.0 feature set. Older cards (GTX 900 and 1000 series, RX 400 and 500) often run smoother on it. If the game fails to start, remove this one.
-window-mode exclusive: True fullscreen instead of a borderless window. Borderless makes Windows composite the desktop behind the game, which costs frames and adds input lag.
-nolog: Stops the game writing a log file every frame. Tiny gain, no downside.

4. Outside the game

Close overlays: Discord overlay, Steam overlay, Nvidia or AMD overlay, and browser tabs playing video. Each one draws on top of the game every frame.
Update the GPU driver: Old drivers are the most common cause of a sudden FPS drop after a Rust update. Get it from Nvidia, AMD or Intel directly, not Windows Update.
Windows power plan: Set it to High Performance or Balanced. Power Saver clocks the CPU down, and Rust is CPU heavy in big bases and towns.
Free some RAM: Rust wants 16 GB. On 8 GB, close everything else, and put the game on an SSD if it is not already; loading from a hard drive causes the long freezes when you enter a base.

Still choppy after all of this? Ask in Discord with your GPU, CPU and RAM and someone will help. Cannot connect at all? See the TPM and Secure Boot connection help.