Half Life 2 & Source Engine Tweak Guide

[Page 4] Patches, Mods & Steam

Official Patches

Valve has released many updates for both the Source Engine upon which the game is based, as well as fixes specific to Half Life 2 and other Source games. These patches/updates are released quite often, and should help get smoother gameplay and resolve a range of bugs. All available updates should be downloaded and installed by all users directly through Steam. Whenever you start the Steam Client, it will automatically and periodically check for and install relevant updates as required - see the Steam section further below for configuration details.

Given Valve's commitment to distributing software via Steam, all updates for Half Life 2 and other Source Engine games will continue to be available exclusively through Steam. Keep an eye on the front page of TweakGuides.com for regular notifications of updates for Half Life 2 and other Source (and non-Source) games as they are released.

Note that if you run a 64-bit based CPU as well as a 64-bit based Operating System such as Windows x64 or Vista 64-bit, you can download the 64-bit version of Half Life 2 for your system. This version will not work on any other type of system, and contains no new content. It simply takes advantage of 64-bit systems to improve performance.

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Copy Protection

Steam is not only a digital distribution method, it also has built-in online verification for copy protection. As long as you've legitimately purchased a game via Steam, allowed it to verify and update online, and you're using your own account to play on only one PC at any time, then you should have no problems at all. An added bonus of playing a game through Steam is that there is no requirement for any CD or DVD to be kept in the drive, and you can play offline if you wish once the game has been updated. If you ever buy a new PC and/or reformat your hard drive, you simply have to download and reinstall the Steam Client, login to your account and you can instantly download and play your purchased games, so there's no concern over 'losing' your games. If however you want to back up your Steam games to CD or DVD, you can do this easily and legally from within Steam itself. Details of all these features are covered in the Steam section below.

A word of warning - be very careful of any methods or software which allegedly allow you to play without Steam, as they are more than likely to be trojans designed to steal your CD Key or Steam ID for example. You risk having your legitimate Steam Account stolen or permanently banned, which means you lose access to your Steam games. For the most part Steam is an excellent and reasonably priced method of purchasing and playing games, so there should be no excuse for pirating these games.


The Source Engine by Valve is a powerful and versatile game engine, and continues Valve's tradition of supporting modifications (or 'mods') for their games. Included with some editions of Half Life 2 (and available as separate games for purchase under Steam) are some existing mods which have been remade based on the Source engine - CounterStrike: Source, Half Life 1: Source and Day of Defeat: Source. If you're interested in developing Mods for Source games, the full Source Software Developer's Kit (SDK) is available for download under the Tools tab in Steam, and includes the game code needed to create Source Mods and edit maps among other features. If you want to learn more about the Source SDK, read the Valve SDK Documentation, and discuss your issues on the Source SDK Forums if necessary.

If you're only interested in downloading and playing official and user-made mods for Half Life 2 and Source Engine games then try the following mods and mod sites:

Half Life 2: Lost Coast

Garry's Mod

GoldenEye Source

Cinematic Mod

Wikipedia HL2 Mod List

Half Life 2 Files

Half Life 2 Mod Database

HL2 Top 100 Mods

Black Mesa Source


Steam is an innovation of Valve's, designed for online software delivery, automatic updates, game authentication and community involvement. You can read about the full history and features of Steam in this Wikipedia Article. Basically Steam is a small program which runs in the background and provides you with the ability to purchase and download full games directly from Valve, it checks to make sure that you are a legitimate owner of any Steam game you attempt to install or play, and it also checks to make sure your game files are the latest version available for that particular game and automatically patches your games to keep them updated. Although you can purchase some Source Engine games independently of Steam, in general it is strongly recommended that you purchase and/or play and update these games via Steam. Below I cover Steam's key features.

To start with, while you can configure most aspects of Steam to suit your personal taste, I recommend that you go to File>Settings and under the Interface tab untick 'Run Steam when Windows starts'. This is because having Steam automatically load up at Windows startup and run in the background is not necessary, particularly when playing other games. Of course if you prefer to run Steam this way, then I recommend manually closing Steam by right-clicking on its tray icon and selecting Exit before you start a non-Steam game - just closing the Steam window doesn't unload it from memory.

If you have any questions or problems regarding Steam, or your game in general, you should definitely make a point of visiting the Steam Support Site. It contains answers to a range of the most common Steam-related questions, including solutions for all the error codes for example, and is always kept up to date. If you find your Steam client is having issues with a particular game download or update, or it won't start, or you're getting an error message, try these Steam Fixes. If none of these solutions help you resolve a Steam-related issue, you can ask for official Tech Support from Valve by using this Ask A Question online form.

To save you some time, here are some quick answers to the most commonly asked Steam-related questions:

Do I have to have an Internet Connection to play Steam-based games: The short answer is Yes, you need an Internet connection to begin playing a Steam-based game. Steam requires online authentication of your game and it may also need to download additional files to activate and complete the game install before it can be played. There is no legal way around this. However once you've registered your CD Key or validated your install and updated the game, you can play it offline at any time without having to have an active Internet connection (see below).

Playing Steam games offline: Once installed, verified and fully updated online, you can play a Steam game without having to be connected to the Internet. To do this, follow the instructions in this Steam Article.

Backing up Steam files: If you purchased a game via Steam and want to back the game up to a CD or DVD there are two ways to do this: Open Steam, go to the 'My Games' tab, right-click on any game you want to backup, and select 'Backup Game Files'. Alternatively, you can go the File menu in the main Steam window, and select ' Backup Games'. You will then enter a backup wizard which lets you choose which installed Valve games to backup, the destination directory, and the media type you'll be using (CD or DVD) so that it can segment the files into CD or DVD-sized portions, ready for burning.

Transferring Steam files: If you have an existing installation of Steam you wish to move to another Operating System (e.g. from XP to Vista or vice versa) or another system, and not just backup to CD/DVD (See below), then simply install the Steam application on the new OS/system, login to Steam as normal, add the game(s) you own that you wish to install and pause or cancel any updating/downloading which commences. Now exit Steam completely (make sure to close the Tray Icon as well) and go to your \Program Files\(Valve)\Steam\steamapps directory in the new OS/System. There you will see all the relevant .gcf files which are needed for the games you want to play. Locate and copy these files across from your existing OS/System to overwrite the files on the new OS/System. Restart Steam, login as normal, right-click on each game and select Properties>Local Files>'Verify integrity of game cache'. Once completed the games should be ready to play.

How do I keep my game updated: Go to the 'My Games' section of Steam, and right-click on the games you want to keep updated. Then select Properties, and under the Updates tab for the game select 'Always keep this game up to date' under the Automatic Updates section. This is highly recommended so that you don't miss important updates. Alternatively, if you don't want Steam to automatically update games as updates are released, select 'Do not automatically update this game' instead. That way you can choose if or when you actually download and install updates. You can see all previously installed updates by clicking the 'View game name Update History' link.

How Do I use Command Line tweaks with Steam: You can enter command line tweaks by going to 'My Games' in Steam, right-clicking on the game you want to tweak, selecting Properties and clicking on the 'Set Launch Options' button. Alternatively you can right-click on the Desktop icon for the game and select Properties, and enter the tweaks in the Target box. Full details are in the Advanced Tweaking section.

In general Steam has evolved to be quite a solid and even quite popular method for purchasing and playing games, so using Steam is only likely to become more common in the future.

The next section of the guide covers In-Game Settings for Half Life 2.