video card problems

I have a new sony vaio, but the video card is only a on-board 32mb which is slowing down my gameplay on such games as battlefield 1942 and medal of honor spearhead. i put in a nividia geforce2 64mb card and the pc recognizes it, but when i plug my moniter into the new slot instead of the original video slot, everything is blank. I need help switching the pc's primary video cards i... i think that's the problem. Thanks.

 

You better disable the onboard video chip (either BIOS-setup or jumper on motherboard - take a look in your manual).