The first computer that my family has was an IBM PS/1 model 2110 with a 12 MHz 80286, 512KB RAM, and a whopping huge 30MB HDD. It also just had the 3.5" "hard disk" floppy instead of a 5.25" unit. This was the first computer I'd ever used. Cut my teeth using DOS 4.00 on that thing, but it did instill that CLIs were useful and not scary. It had a 9" color screen which was better than the green screen Apple IIe units we had at school. I was a little guy back then as I was only six when we got the machine in 1990, but I did learn early how to use it.
Next computer was also an IBM, but a PS/2 running OS/2 2.1 and it had an Intel 80486DX2-50, 16MB in 72ns EDO SIMMs, a goofy MicroChannel board, a 4Mbps Token Ring card, and a 400 MB HDD with some connector that I think might have been SCSI. It wasn't XT type like the 286 had and it was fatter than IDE. This computer was surplus from my dad's office and we got it in late '97 or early '98 IIRC. Big step up from the old 286 but MUCH slower than the Pentium IIs that were new then. I didn't use this machine for much besides word processing as it didn't like the DOS games as much as the 80286 did.
After that came the Compaq K6-2/500 machine in 1999. It was really cheap and we reused the 486's 14-inch monitor on this, but it ran Windows 98SE and I could run new programs for the first time since about 1993. It was endowed with a single 64MB PC100 SDRAM stick on a no-name Super Socket 7 board with some IGP that took 8MB of the RAM. It had a 10GB Quantum HDD that did like all Quantums I've every used did and died, so we put a 20GB Maxtor in there as a replacement. The CD-ROM drive, which was the first CD drive we had in the house, also died and I installed the replacement. Working on the Compaq was the first tinkering that I was really allowed to do on one of our computers and I was hooked. It also had a 56K modem and we were online for the first time too. Got rid of the machine along with the 286 and 486 when my folks moved.
Next came my dad's HP desktop with a 1.8 P4 socket 478 Willy. he'd gotten it shortly after Windows XP shipped, so it had XP Home and 512MB of DDR 266 RAM in it. (Thankfully it was the DDR version of the 845 chipset on that board and not the PC133 version or the RDRAM 850E chipset.) It also had a 120GB HDD and a then-fast NVIDIA TNT2 with 32MB video RAM. We still have this machine and it gets used sometimes, but I think that it will get retired once XP Home no longer gets updates in Jan. 2009.
The first one that I *owned* is my 2002-vintage Gateway 600 notebook with a furnace known as a 35W TDP 2.20 GHz Intel Mobile Pentium 4-M as its CPU. It originally shipped with 2x256MB DDR 266, a 4200 rpm 60GB Toshiba HDD, and had a then-rare ORiNOCO 802.11b wireless card. This machine set me back a bit. Laptops were just starting to get less expensive then, but a good one still cost $2000 or so. The HDD died on me, so I swapped a Travelstar 5K100 in there, and swapped in a 512MB stick of DDR-266 for one of the 256MB ones. Later, I got a *1GB* stick of that stuff from salvage and now it has 1.5GB RAM, which is 512MB more than Intel says the 845MP chipset in the beast can handle. Works fine for me. It also has an Intel 2945ABG WLAN NIC as campus switched to WPA encryption on the APs and the ORiNOCO couldn't do WPA. It was also the first computer I'd ever put Linux on and the last one that had Windows.
The first PC that I built myself is my current Athlon X2 4200+ machine that I put together a year ago. (I'll not bore you with the specs as they're not nostalgic 😀 )I've built a few since then for other people, including a dual socket 604 Xeon server and an Athlon X2 5200+ workstation with 2 2GB sticks of RAM that are very touchy with the voltages. It gets easier every time I do it and I look forward to my next build.