Character animation smooth on old GPU, strobing on new GPU

I've got an odd issue where a character's animation (via unity mechanim) is playing totally smoothly on an old GPU (r290), but appears to be locked at 30fps on a brand new gpu (970m). The total frame rate is nice and high on each platform - maxed out on an oculus headset. So while the game is humming along at 90fps (or something close to that) on each machine, ONLY the character animation is suffering on the newer platform.

Anyone familiar with this issue??