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ㅤI will not be covering how to make an autoexec in this guide. There are many videos and guides that already handle this. All this information is coming from years of playing the game and messing with different things within both public and competitive servers. None of these commands and such will get you banned, but as always use at your own risk. Most of these commands are going to require that you have/use an autoexec, so make sure to have one ready!

ㅤA few of these commands may already be common knowledge but I will still include them in this guide. There are still quite a few that are not common knowledge, so even veterans can still benefit from this guide.

As always, make sure to up vote the guide if you found it useful/good! It encourages people to continue making guides.

Command(s): cl_interp
Default Value(s): 0.1

Description: Interpolation, also known as LERP. In very simple terms, this command adds latency (ping) to everything received from the server. The default is 0.1, which equates to adding 100ms to your latency. You can easily set this to as low as 0.0167 in public servers, which equates to adding 16.7ms to your latency.

ㅤHowever, keep in mind that the lower you set this the less smooth models will move. Common Infected while moving (and even Special Infected) will stutter the lower you set this. The lowest you were able to set this with minimal stuttering was 0.04 (40ms), but as of 2013(?) the lowest you can set this is 0.06 (60ms) for minimal stuttering.

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ㅤTo check if your successfully changed your LERP, you can temporarily enable net graph using the command net_graph 1. Do not leave this on, as it will sometimes impact FPS on a severe scale. For a better description of LERP, check out: ProdigySim's LERP Guide[www.l4dnation.com]. There are other commands you'll need to change as well, such as: rate, cl_updaterate, cl_cmdrate, cl_interp_ratio.

Command(s): snd_mixahead
Default Value(s): 0.1

Description: In simple terms this is essentially LERP but for sound/music. The default value is 0.1 which equates to 100ms of buffering time for audio. Setting this lower will reduce the delay in sounds being played to your speakers/headphones, however the lower you set this the lower the quality of audio will get.

ㅤThe lower this is set, the more likely you are to experience dropped sounds, stuttering audio, framerate drops, and or possible game instability. The lowest I've been able to set this without issue is 0.056 (56ms). This command is reliant on your hardware, so your CPU/RAM/Audio Drivers will have an impact on how low you can set this. This command has been used way back in the days of Half-Life competitive, and is currently used by CS:GO competitive players.

Command(s): dsp_volume
Default Value(s): 0.8

Description: I recently discovered this command and brought it to light to the community. This command affects the accuracy of directional sound in source engine, and is currently cheat-flagged in CS:GO but not in Left4Dead 2.



ㅤI've tested this command for months before publishing my findings. Disabling it makes a difference for everyone but maybe a small handful of people. Both analog and USB headphone users will notice a difference between having it enabled or disabled. However... disabling it is not as easy as just typing dsp_volume 0 into console. This command resets every time you walk into a new soundscape (IE. Walk in to a building/room/outside area). You're going to need a special script to disable it permanently.

Pastebin - Link[pastebin.com]

ㅤTo read more about this, check out my previous guide about dsp_volume.

Command(s): voice_show_mute & voice_mute
Default Value(s): None

Description: This command will print out the current players (Including opponents) into console along with a number representing their voice channel. You can mute individual player's microphones using the command, voice_mute followed by their number. For example, voice_mute 8.
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This will persist through map level changes and even when you return to lobby. If you remain in the same lobby and start a new game they will still continue to be muted. You can unmute someone by using the command voice_unmute followed by their number. For example, voice_unmute 8.

Options(s): Vertical Sync
Default Value(s): Varies from hardware.

Description: Vertical sync locks your framerate to your monitors refresh rate (usually 60) and provides a smoother game experience while attempting to remove screen-tearing[upload.wikimedia.org]. This is great for the absolutely casual player, but absolutely devastating for anyone wanting to take their gameplay ability seriously. Vertical sync will introduce input latency, resulting in delayed actions ranging from jumping, moving, aiming, or anything really.



ㅤThe input latency gained from having vertical sync enabled depends entirely on the game's engine and if they properly do vertical sync. However source engine does it poorly, and having it enabled can result in anywhere between 300ms - 500ms of input lag. That is a half a second of delay before actions are displayed on your monitor. Your mouse is delayed by 300ms - 500ms, so is your movement, and so is the visual representation of your opponent's actions.

ㅤIf screen tearing bothers you, I implore that you look into other options to cap your framerate as vertical sync is a very bad option to have enabled. The input lag added from it just is too impactful for a fast action game. Such alternatives are MSI Afterburner+RivaTuner, DXTory, or NVidiaInspector (if you have an NVidia Card). These are just a few options.

Options(s): Effect Detail & High Paged Memory Pool
Default Value(s): Varies from hardware.

Description: Effect detail and high paged memory pool both control object rendering distance, with effect detail having the most impact. Setting these too low will make props not render at longer distances, and even completely remove props from your view.



ㅤEffect detail, at a very minimum, must bet set to medium. This will have an impact on your frame rate, but it is very mandatory if you ever plan to play anything competitive(IE. Versus/Scavenge). Paged Pool Memory Available refers to your computer's RAM. If you have at least 4 GB of RAM then you should set this to high and just forget about it. A higher setting will allow you to see props from farther away, reduce stuttering, but increase load times.











ㅤMany props in infected only-areas as well as the main path of survivors will become invisible, but still have collision. Meaning you will be walking into these props and be completely unaware that something is in your way, or you're unable to spit/shoot through these. Render distance also affects the Tank's rocks!











ㅤAt lower settings (and not enough high paged pool memory) rocks will be almost invisible until they are already dangerously close. Making dodging and rock skeeting more difficult as you will be completely unaware of where the rock is. This is another reason why effect detail must be set to a minimum of medium.



Just by setting effect detail to medium I am able to now fully see the rock from a safe distance. Further setting this to high will have a bigger impact on FPS, but allow you to see rocks from an incredibly far distance. For most however, medium will suffice.

Launch Options(s): -LV
Default Value(s): Disabled (Depending on region)

Description: This is a launch option available to uncensored versions of Left4Dead 2. This command is currently the only known command to actually increase your framerate. It essentially enables the low-violence or censored version of the game.

ㅤThis command will make corpses/ragdolls disappear near instantly, remove burning infected (Infected won't run around lit on fire, but still act as if lit on fire), remove gibbing (removal of limbs/cuts/wounds) and remove screen blood splatter. Also due to laziness by Valve, mudmen's attacks that place mud onto your screen will be removed as well due to them being the same as blood splatter.



ㅤTo add this command, simply right-click your and select properties. Then select set launch options and add -lv to it. To remove low violence, just remove -lv from your launch options. Enjoy the extra framerate and less clutter from corpses piling up.

Launch Options(s): +mat_motion_blur_percent_of_screen_max
Default Value(s): 4.0

Description: Determines how much of your screen is to be blurred during high motion scenes. Very noticeable at higher graphic settings and when high damage pouncing as the Hunter. A comparison between the option being enabled/disabled can be seen below.











Just simply put +mat_motion_blur_percent_of_screen_max 0 in your launch options.