Rather than spend >$3K on a high-end rig, hoping to make it last 4 years, I prefer to buy a new ~$1K mid-range rig every 1 year/18 months, with one VC upgrade somewhere in the middle.
But that's just me.
Honestly, I wouldn't even try for a job at NVIDIA right now. Go work at your local deli or something, and help out your father. Sounds like he could use some support.
At 19 you have literally loads of time to get your career on track....
You're not going to get a good job (before you're 30) unless you go to college. That's the sad fact.
Maybe you ARE spending too much time on your computer, making freebies to give away. That's a hobby, not a career plan.
If you...
Whatever you enjoy most is what you should use.
To me, changing the settings (at least for the first run-through) is akin to colorizing an old B&W movie (or say... Sin City) where the director painstakingly chose every shade of...