additional monitor to use as extended desktop

Hi, PC HP Compaq running win 7. The PC does not have a DVI Port or HDMI only VGA. It has intergrated intel G41 chip graphics. I used a vga splitter cable to run 2 monitors but they just mirrored. I could not even set separate resolutions. Windows did not detect the 2nd monitor .I downloaded the 2nd monitor’s drivers from the original hp disk but still no joy.
can I do anymore to enable running the 2nd monitor as an extended desktop, or is this not possible because of the graphics and/or no DVI or because the main 22″ monitor is actually a television. Running it as just a mirror of the main monitor is pretty useless. Thanks