Ha, that's hard to read, please learn to type in english when you're asking a question.
And to answer your question, you don't un-install intergrated video, you cant. You probably turn it off in BIOS, or it will auto-detect it when it's plugged in. Just make sure you install the driver for the 1800.
EDIT: Make sure when you install the video card you hook the monitor up to it and NOT the mobo where you plugged it into for your intergrated.