Can't switch graphics card anymore..

I'm hoping someone can help me out here as I've tried Googling my problem but can't find any solution to it.. I obtained my laptop last last night and when I got it there was a small nvidia icon on the right side of the taskbar that would allow me to switch between discrete and integrated graphics modes. It was there until yesterday when I installed nod32, ccleaner, chrome and a couple of small apps. The icon has gone now and I can't figure out how to get it back or how to switch between them any more. The F7 + FN function key also doesn't seem to do anything anymore (whereas before switching graphics modes would make the screen 'flash' once while it adjusted). In the meanwhile, going by my device manager, it only has the Intel hd graphics listed the other one is a standard vga graphics adapter which has a yellow exclamation point on it(my discrete graphics card is NVIDIA_GEFORCE-GTX-460M and it doesnt appear there). Im assuming I'm stuck in integrated mode. This doesn't change if I restart, and dont have a graphics option in the BIOS setup(ao8). Tried reinstalling nvidia 460M driver, it only says 'installation cannot continue. This graphics driver could not find compatible graphics hardware.' I still remember I can access nvidia control panel before.. Does anyone have any suggestions on how I can get my graphics functionality back? Already tried formatting and installing a fresh windows 7 but still the same. No discrete graphics card detected on the device manager.