3x40 - Dragon Ball Z: Dragon Box

The Z Warriors' training proceeds smoothly. Vegeta, who is irate at how outclassed he is by Super Saiyan Goku, has Dr. Briefs build a 300 G gravity room for him and begins training in it. Following some intensive training, he destroys the gravity room, seriously injuring himself. As he lies there, he has a dream about his childhood years, which he spent with his father. Re-acknowledging his princely pride, his fighting spirit burns to surpass Goku.