I have a M4800 which works great. never new what GPU was in it so i simply used the Intel Graphics driver for several years. I read that with the NVidia and AMD GPUs i can run the laptop screen, HDMI, Display Port and VGA port at the same, which is what i want to do. I determined that there was no GPU by trying to install the NVidia and AMD video drivers from the Dell website, but in both cases, the installer told me it could not find NVidia or AMD hardware. I'm running Windows 7 Ultimate and have the latest BIOS (A25). i went out and got an AMD Fire Pro M5100 GPU specifically for the M4800. while installing it i discovered that there was, in fact, an NVidia card installed. since I couldn't get it to work or be recognized, i went ahead and installed the AMD card. On a fresh installation of Windows 7 Ultimate SP1, i tried installing the AMD M5100 drivers - both from Dell and from AMD. both installers said there was not AMD hardware installed. What the heck??? I even tried installing the drivers with the BIOS Switchable Graphics turned on and off. but when i turned it off, the next time i looked at the BIOS settings, it was turned back on. am i missing something here? why would the driver installer say the GPU was not installed, when it is clearly installed? please help