I have a Lenovo Ideapad Y460 running Win7 x64 SP1, with switchable graphics - Intel HD / Mobility Radeon 5650.
When I tried to update my Intel hd graphics driver through Device Manager (Display adapters, right-clicked Intel HD Graphics, Driver tab, "update driver", "search automatically for updated driver software"), Device Manager for some reason changed "Intel HD graphics" to "Standard VGA graphics adapter" and resolution became 800x600. I rebooted, but after that, I couldn't roll back the driver (button was greyed out in Device Manager).
I first tried the HD graphics driver from Intel's website for my processor (i5 430 M) but that had a driver signing issue. After disabling the driver signing enforcement, it led to the no-display issue, details in the next paragraph.
I subsequently tried to install the Intel HD Graphics driver from the Lenovo support site (IN2VDO26WW6.exe), but after rebooting, there is no display after the "Starting Windows" screen. The sound at the login screen plays, and I can enter my password and have it log in (based on sound cues), and apparently everything loads fine (can shutdown using Run command), just that there is no display.
I have tried setting my laptop's date to near the driver's date, to no avail.
I have tried deleting the registry keys at:
HKEY_LOCAL_MACHINE/Software/Intel/Display HKEY_CURRENT_User/Software/Intel/Display HKEY_CURRENT_User/Software/Intel/ICC/Applications/Intel Graphics Driver
and reinstalling the driver, also to no avail.
Booting up from a Linux (lubuntu) livedisk thumbdrive works, with 1366x768 display resolution.
Any help would be greatly appreciated.
Thank you in advance.
I have asked the same question on Lenovo's forum, but have received no replies...
(Yes I did a very stupid thing that caused this whole mess. :C T_T )