EVGA GeForce 6200 512MB AGP Video Card?

Okay right now i have Nvidia geforce fx5200xt agp. i want to upgrade the ram and i know that evga has 512mb so will i be able to just plug it into the slot and install??? i dont want to have to buy it and leave it in the box. i would appreciate any helpful advice.|||if you want to replace your video card you have to turn off your computer unplug your current video card take your new one put it in that slot turn your computer on and install the drivers for that video card :3