Getting every last drop out of your linux game

Alright, say you want to play a fullscreen game in Ubuntu, one that's hardcore on the system resources, and you want a totally lag free game (or at least as fast as possible).

Window Manager/Desktop:

Here's something I do to make sure almost nothing else is running (well, nothing I don't need for a gaming session). First off, on your initial ubuntu login screen (gdm), click select session and go with like failsafe terminal. This way, not even a window manager is running. In this terminal type in: "nm-applet &" so you get your networking (if you use wireless anyway like I do). The & lets you execute another command. Then just run your game from the terminal, and you can be pretty sure that it's going to run smoother since you aren't running anything practically. Another thing to try is to pickup a "lightweight" desktop/windowmanager solution. Such things save you alot on memory. From my testing the most light desktops would be fluxbox/blackbox, lxde, or icewm. If your wireless networking isn't coming up in those, just run nm-applet. Whatever you do, do not run compiz (desktop-effects), and you should notice a big difference when you are gaming. And try to stay away from kde aswell, as it is pretty, but it does eat resources. Try to stick with something simple, no SVG wallpapers if any, I suggest just a plain color for a background.

Drivers:
Make sure you have the latest and greatest drivers for your videocard even if you have to download and even compile them yourself. Be carefull with beta drivers that aren't tested well yet, keep a backup on hand of the old drivers in case you run into issues. Get your nvidia drivers directly from nvidia as soon as they are released and I also suggest their beta drivers if you are a more advanced user. If you are building a system for gaming, do yourself a favor and do NOT buy anything but nvidia hardware for linux. ATI drivers are just a joke. Do not put yourself through the pain of being an ATI owner. Stay away from laptops with intel or ati video chipsets, you will just regret it, trust me. My wife has a new radeon HD card that has better specs/reviews in windows than my nvidia 8200M G on my laptop, yet mine smokes hers in ubuntu 9.04 at litterally everything.

Memory:
You know, I have 4 gigs of ddr2 in my new laptop (on ubuntu AMD64), and while running a memory intensive game (secondlife), firefox, thunderbird, my twitter client, pidgin, and a couple other things, it uses about 1.5 gigs of it, and my swap partition remains empty most of the time. Try to have at least 2 gigs of ram for gaming, though I always max out my systems for the motherboard specs myself so I don't have to worry about it later.

CPU:
I strongly suggest at least a dual core cpu at least, at least rated at 2ghz, with this kind of power you should run just about anything linux games wise just fine (until maybe rage comes out, since it's IDTech5, we don't know what it will require).

Linux Gaming Vs. Windows Gaming:
Unlike windows, you notice a gaming machine for linux doesn't require much in the way of an expensive system. My linux gaming rig costed me total of 500 dollars after memory upgrade and a *good* cooling pad. The reason you don't need as much is linux doesn't use as much resources to run, and you aren't running any virus software or anti-malware software at all. That virus software eats up resources, and is practically a virus itself in the way of it always sitting there slowing down your computer scanning every file before you click it, scanning your emails and websites. Between that and windows memory managment is why you need to build a 1000 dollar machine that runs as hot as an oven just to squeeze out a few fps in a game. And not to mention, most linux games tend to be coded in C, C++, etc, and run rather fast compared to say some crytek engine that most likely has sloppier code than a first year programming student at some unaccredited online college. Then you play a game like Doom 3, on linux or Quake Wars, and watch how with doom 3, you don't even need a dual core, and it runs like silk, on quake wars, you don't need a 1000 dollar machine, it just works.

Why aren't there many (commercial) linux games?
Alot of people say linux isn't for gaming, and why they say that is, many commercial games are only made for windows. Why is that? Well, more people currently run windows. If more people ran linux, there would be more games. If you want to get more commercial games on linux, show them, and buy linux games. If Tuxgames.com or Linux Game Publishing start cranking out big money from linux game sales, they can get more money to get rights to port more games, and it would also show the market that linux people want games too. You would be surprised at how many companies sit on the fence on linux, they want to, but they don't know how much it's going to pull in. If you show them buy buying out tuxgames's supply of games like hotcakes, this will send a loud message to the companies. It will be something like, "Hey, we PAY for games if you make them. We are a market here too! We pay for quality!!". ID Software keeps porting our games because we keep buying them. They know we keep buying them because we are always hitting their FTP's to get our linux installers and patches. They know we appreciate them, and we pay for our games. It might not work into your ethos about paying for a game, but, if you don't, you can't complain that we don't get any.