Higher vccd voltage on radeon rx 480 nitro since 17.4.1 driver

I am using sapphire nitro rx 480oc version. Until 17.4.1 driver core voltage was 1.875 under max load. And tempreatures were max 67-68 celsius,

Since 17.4.1 driver my core voltages reaches 1.21 . This is causing higher temperatures. 70-71. I have tried 17.4.3 and 17.3.4. its the same.

When rollback to 17.2.1 everything is normal. any idea for soemthing i can do or its some driver related problem.