Poppy Ult Lag Spike

Hey, Every time I charge Poppy's ult, my ping shoots up to like 2k. It happens to Zac's E as well, but when I turned off vertical sync that problem was fixed. I have no idea what to do about Poppy's ult though. Does this happen to anyone else or is it just me? Please help I really like the new Poppy, but this problem makes it really difficult to play her.