Is this graphics card alright for gaming?

I don't care if it's the BEST, but if it's better than the stock Dell Optiplex GX620's stock graphics card, it'd be good. I only get around 1-5 FPS on EVERY game I play, ranging from Minecraft to Team Fortress 2 to Left 4 Dead 2. I also don't care if the graphics are great, either, as long as I can play the game better than this. I'm good on RAM, I have about 3 Gigs and nothing I play has exceeded that so far, but I want to know if this graphics card: http://accessories.us.dell.com/sna/productdetail.aspx?c=us&l=en&s=dhs&cs=19&sku=A7010917&mfgpid=167263#Overview

I want to know if it's capable of running things like Minecraft, Team Fortress 2, Left 4 Dead, if it's good for watching Youtube and Netflix in 720p instead of 420p.
Thoughts? Or is there something better that is compatible with my pc, and still fits in that price range of 100-200$?

Added (1). Also, is there a place where I can get cheap SATA cords to hook up a second hard drive?

Guest

Personally the gx 620 is getting long in the tooth for gaming its ancient and uses pentium d as its max upgrade

also depends what model of the gtx 620 you have

personally id save up and build this if you have the big tower gtx 620 with the atx power supply you can
grab the power supply and the graphics card now and put it in your current system then save up for the rest of the stuff
http://pcpartpicker.com/p/qpV7GX

your old system will play older games well but newer games i wouldnt even bother youd get low and probly have to tonne down alot

the new build will play games on a high setting and most new games well

Bringing Salvation