Need some help picking parts

Hello, I am a console gamer looking to move to pc gaming. That being said, since i am from console i really have no idea of what to build for a decent pc. My budget is $200-300, and i already have a case, and some random parts such as a power supply, a graphics card, and some ram. These parts are pretty strange, someone gave them to me so, some of it is off-brand stuff, and/or old. Does that matter? Also is it possibly that someone would reccomend a decent build within the price range? -Thanks it helps a lot!

Parts i have: 

Power Supply- Orion DFS802012M

Graphics Card- MSI NVIDIA GeForce 8500GT 512MB DDR2

RAM- G.SKILL Value Series 8GB (2 x 4GB) 240-Pin DDR3

Case- I am unsure about.... The exterior is 18 in. x18 in. and 8 in. deep.

Forgot to mention, I do also have an optical drive ;)

Also, if these parts aren't very good please, by all means suggest different ones to replace them with.

Again, Thanks!

Please list the specs of the power supply, graphics card and ram. What size is the case that you have? 

 

Worst case scenario if you're not able to salvage any of those parts, this is what you can get for that price range.

http://pcpartpicker.com/p/LfgV

Parts are now listed. Also thanks for the build!

What is the resolution of your monitor? If you got any...

 

i have one asus 23" monitor that does 1920 x 1080..... at least i think so :)

http://pcpartpicker.com/p/Lgpc

Nothing stronger than 7770, that kung fu PSU will barely be good for this build

Changing PSU should be first on your list of changes

Sweet thank you!

+1 here except now pcpartpicker has an x4 965 BE for like $89 or so.

And if ram speed is a concern, they have other AM3+ socket boards that support higher frequencies, but they won't support 32gb like the one Miskonius listed and it wont have usb 3 etc..