Im making a new gaming computer and wanted to know what would be the best to go with now of days. My budget is $900 and hopefully that will get me a gaming computer that is able to run "BF3" on high.
You would have much better luck posting in the systems section. They're are plenty of people their willing to help people put together builds. They have template somewhere that you can fill out that you can use to provide users with information about how much you want to spend, the main purposes of the computer, parts not needed, where you would like to purchase the parts from etc.
Have a look at Tom's Guide to Graphics Cards - it can give you a good idea of what you can get for your money. If you have a particular goal, then determine which video card you'll need, and start there.
It is easier to run a game on "High" if you are painting fewer pixels. You wouldn't be able to paint 2560x1600, but maybe 1680x1050, or even 1280x1024, might make it possible.
Once you know the resolution and the video card you want, you can build a system around it.
There are many cheaper parts you can invest in that'll give you a high quality computer. There are parts I would avoid, however, such as an SSD. Parts like this won't enhance your actual gameplay (minus loading time) and will bump the cost of your system up $100+.
Follow CompulsiveBuilder's suggestion of referring to "Tom's Guide (...)" so you can get a base understanding of what you're doing. Post in the Systems section for questions about your build. Good luck
Intel Core i5 2500k 219$
DVD/CD R+RW 20$
a good case 65$
cooler master 92mm CPU cooler 33$
Seagate 1TB 60$
Corsair 8(4X2)GB memory 55$
MSI P67A-G43 (B3) ATX Intel Motherboard 129$
COOLER MASTER GX series 650W PSU 74$
EVGA GeForce GTX 560 Ti 1GB Video Card 240$
TOTAL 896 $
this CPU will play all new games at ultra settingd