Pentium 300's to today...
Woefully outdated information; I've no intention of updating this.
A little while after I arrived in the US, I forked out a considerable amount for two Pentiums, a 300 and a 266. Each had 128MB RAM, 8GB hard-drives, 8MB video cards by 3DLabs (Permedia 2's) and Voodoo 2's. One had a DVD-ROM drive with decoder card, the other had a CD-ROM and a CD-R drive.
I also had two NIC's installed so me and my wife could play networkable games together, as well as do file sharing. I also upgraded to Windows 98. Armed with these toys, I bought a large number of games. Games are considerably cheaper here in the US, even accounting for currency conversion, they are least 40% cheaper than in Australia.
I bought and played Quake 2, Unreal, Deathtrap Dungeon, Blood and Magic, Blood 1 and Blood 2. I'm sure there were others, but these are what I can think of off the top of my head. Blood was a hoot game. It was based on the Build engine used by games like Duke Nukem 3D and Shadow Warrior. You played the somewhat undead Caleb; a wise-cracking gun toting slayer. It is a 3D shooter, but it was done with such black humor and a cool sense of noir that it remains a classic in my books. It was damn hard in places as well; those phantoms were a mongrel and a half to kill.
A game called Half-Life came along that rocked my world and the world of many others. It was just so damned fine a game. It had everything you ever wanted in a shooter. More on this game later, as I'm writing a seperate adulation for it.
It was about this time that I got broadband. Yep, DSL...didn't that make gaming a new and utterly more rewarding experience? It did. For once, I could compete on an even keel in games like Quake 2 and Half-Life online. The benefits of broadband are legion, not just for gaming obviously. It was close around the time I got DSL that I was introduced to Ultima Online and Everquest.
I played Ultima Online for a little while but to me it seemed a corruption of everything I knew about the Ultima's. By introducing it to a large audience, it was watered down and Richard Garriott's vision of Britannia was pejorated into a world of lamers and killjoys. No doubt Star Wars: Galaxies will do the same for George Lucas' milieu.
My Pentium's were showing their age, so I upgraded both systems to Athlon Thunderbirds, a 700 and a 900. I still have these today and they do fine, even with 2.5GHz processors for sale out there. I've yet to play a game where the Athlon 900 wasn't sufficient to run it. (Update: I recently built a Pentium 4 2.4GHz to make matters a little more future-proof).
No doubt I'll need to move along in the future. The computers I have today are equipped with GeForce 2 64MB video cards, 384MB of RAM, a 40GB hard-drive and a host of add-on's like webcams, printers, scanners and a digital camera.