GTA III PC video memory problem?

okay so im setting up gta III on my fathers computer and this is what happens. i try and run it and it says that it need at least 12mb of available video memory to run. so i go into the BIOS and i allocate 128MB of memory for the video just to be sure i have enough and it still says that it needs 12 mb of available video memory even on startup before i try to run anything i try GTA III and i still get the same error. Any Suggestions???