A week ago Microsoft decided to upgrade my PC, before you know it there is Windows 10 and I have been suffering since that day. First issue was that my descent Switchable graphics driver, that was running fine with Windows 7, doesn't work anymore. Actually Win 10 says there is no Hardware with switchable graphics capability.
After days of pain, I found a solution. My problem was that the Intel drivers are not properly installed or working. Most people think AMD/NVIDIA drivers are having issues. But in reality Intel is not supporting GPU switching in their drivers and AMD is not serious about signing all their drivers, especially the "atikmpag.sys" that comes with Intel drivers with switchable capability. If you visit Intel web site it says it's not supporting graphics switching for win10, see below
So if you put your Intel driver which actually tells the OS about the switching ability, in win 10 nothing happens and you won't see the sweet switchable graphics option in your Power Options too,
So the million dollar question: How to solve it?I will tell you what worked out for me.
A word of caution:
Note that the following method may run you into a state where the Windows will be struck at a black screen after Logo, so be prepared for the worst.
While testing this one of my PC even said the Display hardware is missing. Its better to have the AMD/NVIDIA Driver installed and updated. You can install Intel first but its quite risky.
So once you have the right AMD/NVIDIA driver installed and updated, proceed with the following
1. Delete all drivers related to Intel Graphics.
2. Start Windows 10 with Disable Driver Signature Enforcement in Advanced Boot Options (here)
3. Install Intel Drivers from your PC Manufacturer's website (the one with graphics switching). I used my old win7 driver and later updated with the new ones from Intel Website.
(While installation your screen may be switched of and on several times. In-fact one PC repeated the whole installation process over and over again, don't bother just go ahead and restart)
4. Restart your PC, and you will see the Switchable Dynamic Graphics back.
I thought I should share the info. May be people better than me will get you guys a better solution.