Ahhh.... The memories!
I'd say I started with a Sinclair ZX Spectrum in 1983. The kind with the tapes and all... I remember playing stuff like "Bruce Lee" and "Elite" all night long.
Then it was a 386. Great for "Wolfenstein" and "Doom"!
Then I moved to a 486, then to a K5-133.
For a short while I had an MII-300.
I'm now using a k6-2 450 and a PIII-650.
Life is good!
BTW, the first computer I EVER played with was one of those using perforated cards. I hazily remember (around 1978 or 1979) playing some "Space invaders" stuff and the other game (what's it called? two guns shooting at each other, and you have to control the angle and speed).