What 1700, T-Bred (A/B) or Palomino? They run at different voltages.
If it's a T-Bred A, up to about 1.7v I think should be fine, since if I'm not miskaten, default is 1.5, so 1.7 should be fine, not over 1.8v though.
My Palomino at stock speed is 1.78v, so you should probably be able to go to 1.9 maybe a bit higher fairly safely.