Upgrading the computer internals is entirely up to you. I myself enjoy working on computers and I find that buying the exact parts for your needs is a great benefit. I chose to buy a refurbished dell OptiPlex 760 direct from Dell. I ended up upgrading the video card, ram, adding a second hard drive, upgrading to Windows 7 Ultimate 64Bit from windows vista home basic, and changing over to a core 2 quad instead of a core 2 duo. As I stated it is all up to you. If you don't have experience with the inner workings of a computer then I don't recommend changing parts yourself. I hope this helped good luck!
My Rig
Dell OptiPlex 760
Windows 7 Ultimate 64Bit
Intel Core 2 Quad Q9550 at 2.83ghz
8gb Kingston HyperX T1 Series DDR2 Ram
Nvidia 650 GTX 1gb Video Card
300GB WD VelociRaptor 10K rpm HD
I have 3 Dell towers, the latest one being a dimension 3000. I,m trying to stay under $800 but also be cost effective. I've heard I could get more bang for my buck by rebuilding? Photos and Music are my thing and yes I have tools.

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