My Acer Aspire 5755G doesn't detect nVidia GT540M GPU


Sep 20, 2015
Hi everybody! I have an Acer Aspire 5755G ( i7-2670QM 2.2GHz - 6GB RAM DDR3 [ but it reads only 4 GB, don't know why ] - Windows 7 Ultimate SP1 x64 bit ) with an nVidia GeForce GT540M on it, but the system doesn't detect the gpu. Currently I'm running with the Intel HD Graphics Family ( because it's the only one that the system detects. In the BIOS, graphic mode is on [Switchable] but dxdiag doesn't detect it neither ( i tried also with CPU-Z but neither this one sees the gpu ). I tried to install all the drivers for my laptop from both Acer and nVidia websites but the installers always give me the error "This graphics driver could not find compatible graphics hardware." If someone has an idea of what else could I try to fix this problem, come forward and speak! :D
Thanks in advance for whoever will answer me ;)