For sale only bios mod for e-mail.
Make Asrock Z170 Extreme4 like Z370/Z370 and use processor Cofee Lake 8700K/9700K or any more Coffe Lake i5/i7/i9.
Except modbios you need programmer CH341A to save bios mod and modify pads in processors. More you will find in google.
Biosmod also available for all Asrock and other Z170/Z270/H110 motherboards. If you need any, send message.