No, it's ok actually. Load Line causes the vdroop, you can turn LLC on to counter it. And yes, you should definitely set the voltages manually. Start from 1.3V on vcore and 1.21V for VTT. When you get it stable, try reducing the VTT till you make it unstable. Note that IBT isn't the ultimate tool for testing stability. You will also need 8h of prime95 to make sure it is stable over the longer period of time. Set your memory voltage to 1.65/1.64V too.