Today I installed Windows 8.1 64-bit on a HP G62-b63SG notebook. Everything went fine and all devices were identified correctly – until the notebook activated the suspend mode and I woke it up again. The screen was black now and seemed to be turned off, while the machine was running… Well, at the first moment I thought that the display was turned off and not reactivated, but it was not the case! Only the backlight was off, which I realized in a lucky break…
I have not found any detailed solutions that helped me. So I decided to install the following Windows 7 64-bit drivers from the HP website:
Intel Graphic driver (64 Bit)
2011-03-07, Version 18.104.22.1689, 39.8M
ATI Mobility Radeon HD 5470-Graphic driver
2010-11-12, Version 8.771.1.0, 197.7M
The Intel driver told me that there is a newer driver version installed, but I installed the older version anyway. After the installation the backlight directly became enabled. And this was the solution! But I executed the ATI dirver setup too!
I don’t know why the newer drivers could not handle the backlight after waking up from suspend mode. I have not found any log or message in the event log. I hope this helps others!