Does the Binatone tennis console count?
If not then it's the ZX 81 (16K?) then a Spectrum.
The first REAL computer I had was a 386 DX40, then a 486SX25 upgraded to DX80, then a P166, P200, P2 333 celeron, P3 500.
In those days I was always upgrading something - chips, graphics, motherboards, RAM etc.
My current machine is a P3 800 with 64MB GEforce2 graphics - had it for about three years. I know it's really outdated now but I just can't afford to upgrade. Seems to run everything I want though, even most modern games (on reduced detail).
The need to upgrade seems to have slowed a bit.