some have 4 ram slots but you would try both ram slots using 1 stick each time. And yes the graphics card cant go anywhere else so the only way to test is to lend one or buy one
. I cant seem to find any specs for that IBM pc...any numbers on the motherboard?
Also the connector on the graphics card do you see one in the section with all the other ports like where the mouse plugs in etc if so you might have onboard video too.
Also yes ram only goes in 1 way if it doesn't click its not right