Making A fast gaming computer  

I know a really great site that builds a PC for your standards, so all you haveto do is cutamize the PC to how you want it, they build it and ship it to you (world wide). Its just really really expensive, but if you are willing to pay that much for a great gaming PC then its worth it. http://www.alienware.com.
If you want to buy the parts and hardware and build it YOURSELF then I have a few tips that might help.
For a great gaming PC you need really great graphics so try buying 2 graphics cards, Nvidea 8800/8900 GT and make them a dual so you will have double graphics! To have a good performanced PC you need a really good quality and performanced motherboard. I dont know motherboards that well but get one that can take more then one processor and about 4 slots to fit your RAM into.
Next I recommend having about 2 GB of Ram you dont need anymore unless your going to do much more then just gaming, im talking work, internet, movies, music and all. Then you should get 4 x 1 GB RAM TURBO or 2 x 2 RAM NORMAL.
Next to store all your games you need a really good Harddrive. You need the speed, the space and the queality. Get a fast running harddrive with loads of space I suggest about 500 - 1000GB of space. Also instead of installing your OS (windows) on the Harddrive try looking for a smaller harddrive like a 20 - 40 GB to install the WINDOWS files so you dont get it all mixed up with your media and gaming files.
You need a good OS (operating system). Although loads of people are saying that windows vista is really bad with loads of bugs etc. it acctually isnt. Especially windows vista ULTIMATE. It also gets updated every week so windows vista will get better and better over time. If you dont like windows vista then use Ubuntu which I heard is really good, better then any other OS. And its free to download.
Get a good PC Case. I wouldnt know which one to suggest since I dont know what you like so go browse for a nice, big and fancy PC case to put it all in.
Every gaming computer needs a nice, fancy big screen. I have a 22" acer monitor which is really good for games. But now a days the HD monitors are really big so look for one of those in the range of 17 - 24" HD, blueray compatible.
For really good speakers I suggest logitech, they have really good variety and loads to choose from, all good.
And last but not least, you need a DVD ROM drive to put your games in . I heard that they just brought out a blueray DVD ROM which is amazing and really fast, also good for burning CD's and DVD's. (Double the speed then any normal DVD writer).
This should be all of it. This might cost quite a lot of cash... Acctually alot alot of cash Just a referance so you know which is best otherwise just go to alienware and get it all faster.
Hope it isnt to much information C ya round!

you know what you need,why do you tell dell,they will make a good and cheap pc for you . i belive dell.

Frist off if you want a decent gaming machine without being overcharged make a home-brewed and never by oem 90% of the time you are paying anout 20-30% more for nothing but i new and contact agreements. Or if you don't want to build it, by the parts and take it to a small computer shop. Also becareful on how high end you go because sometimes prices can drop very fast. Also keep in mind the higher end graphics cards are nice to have but the games out may not use all the power and coming games for the next year my not use it and the price dropped by that time. Over all it depends on what games you have in mind and how much your willing to pay.

The first thing that you should choose for your gaming computer is the processor you're going to be using. If you want to have a computer that is going to be able to run games that are released for several years, don't hold back on this. I'm planning on installing an AMD Phenom 9600 quad-core processor in the computer I want to build. It's an expensive processor, but it's the fastest available. If you want to get a bit cheaper model, you can get the Phenom 9500 quad-core instead. It's about $30 cheaper than the 9600 at Newegg.com.

Once you've chosen your processor, you can choose your motherboard. The reason you want to choose the processor first is so that you can choose the motherboard based on the processor's connection. The Phenom processors are both socket AM2+ components, so you'll need an AM2+ compatible motherboard to run them. I want to buy the MSI K9A2 Platinum motherboard, which is AM2 and AM2+ compatible and has room for up to 8 gigabytes of RAM.

Once you've got that figured out, you can choose the other parts for your computer. You'll need things like a hard drive, RAM chips, cooling fans, a graphics card, a sound card, an Ethernet or wireless card, a power supply that can provide enough power to run all of the components in your computer, and a case to hold everything. You should also choose a monitor, keyboard and mouse, and a DVD drive for the computer so you can install your games. You'll also need an operating system. I'd recommend choosing that based on what the requirements of the games you play most often are.

Building your own computer can be a great experience, and it can help you save quite a bit compared to a prebuilt computer. Good luck with building yours!