Parabolic moves are often followed by violent pullbacks due to the fact that these stocks tend to be very overbought. However, once the overbought condition is alleviated these stocks tend to go straight back up. That is why I recommend investors/traders pay attention to Nvidia, it's in the process of pulling back.
If it continues to pull back the risk associating with purchasing this stock diminishes and thus would be worth a purchase. However I would personally prefer at least another 20% pullback before I start considering this a buy for my own trading system.
Regardless of what happens, in the years to come Nvidia will likely be trading higher much like Tesla and Apple.