I was running El Capitan on my Lenovo Y50-70.
I downloaded the High Sierra update and ran it.
Whenever I select the "Update to High Sierra" option in Clover UEFI, the laptop reboots right away going back to clover and when I try selecting the update option in clover again, I get the mac screen...
I originally set up my lenovo y50 with El capitan using the wrong SMBIOS.
When I noticed, I changed SMBIOS in the plist, and also added a corresponding Hardware UUID.
The change shows up in Clover-->Options-->Smbios, and in El Capitan in system profiler.
After the change, however...