Commodore 64 from the time when processor speed wasn't even discussed just the whooping 64 K of Ram.  Had an   external 5 1/4 drive.  Only took 5 minutes to load some of the simplest games.  Lot's of lockups and I'm just very thankful I didn't have the tape drives.  Up to 45 minutes to load data.  But the second you turned it on it was on. No Post ;D , no loading windows , just turn it on and go.  It even used Atari controllers for games.