NES
Yes, I'm old.
Right there with ya!
I grew up with an Intellivision, Atari 2600, and NES. Couldn't tell you which was my first, I'm pretty sure my family had all of them before I was born or right around that time, lol.
My very first gaming systems that were ~my own~ were my yellow Gameboy Color and my purple Gamecube, both of which were gifts around the time I was 10.
Everything prior to that was more of a 'family console', but by then I was the only kid left at home and my parents didn't play as much.