Ati radeon 9600 video card not working
 

I have a pm4dpt motherboard and I am trying to get this ati radeon 9600 to work with it but I am not having any success with it
The on board vga is working but when I try to use the agp card I get a message on the screen something about "cannot display this video mode"
In bios I have the option of selecting onboard, pci or agp this is for "Initial display" which I am not sure what it means.
Does that mean that initially starts in one mode and then switches to another mode ?
If so what determines when to make the switch ?
Somehow I don't see that working unless the agp card has a bypass for onboard vga
Another question is do the drivers have to be installed in order for this card to be able to display anything on the screen like the bios for example ?

You should ALWAYS install the drivers with the video cards you purchase. And some video cards need you to install the drivers BEFORE you install the video card.

I appreciate your help.
Normally I would install the driver before using it but since I bought the pc used it did not come with it so I tried to download it but I did not have any luck in finding the right driver for this video card
What is confusing to me is the title "initial display" in bios I think it should say something like "select display" or something like that
"initial display" to me it means that initially it will use the display chosen Ok but what happens after that ? Does it switch to another display ? if so at what point ? If not than why call it initial when it stays permanent until it's changed in bios to a different display ?
Right now I am using the onboard display and it's seems to be ok with what I am doing so far I just wanted to see if I cen get this card to work in case I need it or just throw it out and get a new one if I need it