When I started, about 6 weeks ago, I'm guessing I was delegated about 30SP. (Maybe a small amount was gifted, but I really dont' remember now.) I started noticing the bandwidth issues when I went down to 27SP. It bottoms out at about 15 which will remain delegated for awhile.
Now, as you start powering up, you won't get the full benefit for awhile, because Steemit's delgated SP will decrease - still leaving you with 15 until your powering up gets you above 15... then, you start making real progress.
BTW, although some people say that bandwidth is purely an allocation and waiting game, it isn't... For me, the worst time of the day is first thing in the morning!!! (When, in the evening before I went to bed, I was at full bandwidth!) Rather, the bandwidth thing seems to be a priority status. I.e. when you're still low on the totem pole, you only get bandwidth when there's enough to share. (Other users aren't using all of it right now.) The worst I've had to wait was 10 hours one day when it was 5pm before there was enough bandwidth for me to get my turn! But the more SP you have the higher priority you have for bandwidth. That is why you need to power up (more than any other reason!)
I hope that helps.
RE: i just upvoted someone and their balance went DOWN 1 cent !!! ???