I need 1.275 VTT for 19x200+HT. I'm actually backed down to 21x180+HT right now though but still at 1.275 VTT because I didn't feel like figuring out if a lower value would work. I required 1.375 VTT for 20x200+HT in Prime blend and I think the bump to 1.395v helped with 21x200+HT.