I have a y510p with a single 750m, so it is using the Intel graphics primarily. The Asus PB278Q monitor is correctly detected over HDMI, correctly recommends a resolution of 2560x1440, but when I enable the output in any mode (single, duplicate, or extend) at any resolution (even very low resolutions), the monitor displays only black. A signal is detected by the monitor, but it actually makes the monitor not able to open the menu or switch inputs until the HDMI cable is removed or the output disabled. As far as Windows is concerned everything is fine, as it thinks the display is working and asks to confirm the changes. My colleague has a y500 with SLI 650m, and as I understand it the primary display is the actual 650m, and the same monitor works fine for him. I imagine if I was able to disable the Intel graphics completely, or stick a second 750m in the ultrabay (which I do not have), it would probably work. I've tried on both Win7 and 8, and on both the drivers provided by Lenovo and updated drivers from Intel and nVidia. Is there any way to force disable the integrated graphics? There are no relevant settings in the BIOS that I can find. Is there an unlocked bios that might provide such an option, or any other ideas of things I could try?