Thanks to standardization, building a computer is like legos. Each part has a socket which can house other parts. Make the sockets match and voila, it just f'ing works. Building your own is cheaper if and only if you can provide your own OS and accessories (mouse/keyboard/monitor). Having the cost of the OS/monitor in the build will weaken your computer.
Performance of games is much more heavily influenced by the graphics card than anything else. Performance of the OS is limited by the CPU and hard disk. Given your price range and the fact that you will need a monitor, you should be looking at an Athlon X4, GTX 470 graphics card, 3-6GB of Memory, and a 64 bit OS. Usually around $800 - $1300 will get you a best bang for the buck system. Anything above that and you will be looking at higher performance parts (SSD instead of traditional magnetic storage, higher rated memory, motherboards for overclocking, etc.). SLI/Crossfire is never worth the money unless you're using two extremely high end graphics cards.
The usual breakdown for a gaming platform is like this:
10% of cost = motherboard
10% = power supply
10% = Hard Drive
10% = Case
10% = Accessories
5% = Memory
15% = CPU
40% = Graphics Card
Sites to check out for reviews:
anandtech.com
tomshardware.com
firingsquad.com
Sites to buy parts:
tigerdirect.ca
newegg.ca
Good luck on reviewing.
As far as building the computer, the motherboard manual is usually pretty specific unless you get some crap no-name brand from Taiwan. There are also plenty of tutorials on Youtube for how to install/replace parts if you get lost. Plan to spend 4 - 6 hours building the computer your first time. Subsequent builds will only take 1 - 2 hours. The most important thing about building a computer is preventing static discharge and making sure you're grounded to the case before doing any work on the computer.
Performance of games is much more heavily influenced by the graphics card than anything else. Performance of the OS is limited by the CPU and hard disk. Given your price range and the fact that you will need a monitor, you should be looking at an Athlon X4, GTX 470 graphics card, 3-6GB of Memory, and a 64 bit OS. Usually around $800 - $1300 will get you a best bang for the buck system. Anything above that and you will be looking at higher performance parts (SSD instead of traditional magnetic storage, higher rated memory, motherboards for overclocking, etc.). SLI/Crossfire is never worth the money unless you're using two extremely high end graphics cards.
The usual breakdown for a gaming platform is like this:
10% of cost = motherboard
10% = power supply
10% = Hard Drive
10% = Case
10% = Accessories
5% = Memory
15% = CPU
40% = Graphics Card
Sites to check out for reviews:
anandtech.com
tomshardware.com
firingsquad.com
Sites to buy parts:
tigerdirect.ca
newegg.ca
Good luck on reviewing.
As far as building the computer, the motherboard manual is usually pretty specific unless you get some crap no-name brand from Taiwan. There are also plenty of tutorials on Youtube for how to install/replace parts if you get lost. Plan to spend 4 - 6 hours building the computer your first time. Subsequent builds will only take 1 - 2 hours. The most important thing about building a computer is preventing static discharge and making sure you're grounded to the case before doing any work on the computer.