My first PC was a 386DX40 I built for games school work, which I was able to replace the next year with a 486DX266 built for Doom school work, both thanks to getting a holiday job at a PC company. I still remember the trip to London with some college friends to go to a big computer expo we'd blagged our way into, where I bought my Soundblaster AWE32!
The first PC I had access to was an Amstrad 1512 that resided in my dad's 'office', and which replaced the Amstrad PCW 9512 (fond memories of 'Starglider' on that one!).