The title of this thread is how I got into Retro-PC's actually.....EVERYTHING I've had up until about the past six or seven years was old when I got it....
Main computer 1998-2001 - Tandy 1000 SX with 384K (later 640K RAM) - Granted, I did not use internet at home back then, mostly all I did was classwork and play old DOS games on it. I remember the teacher was tripping at how all the kids in his class turned in their homework on regular printer paper in Times Roman font, then here I am with a 12-pin Dot Matrix printout in standard 80x25 column text on pinfeed paper.
Main Computer Feb-July 2001 - Flight 386 SX - which I used as a 386 SX for a week, then yanked the motherboard and threw a ZEOS 386/486 upgradeable system's mainboard with a 486 DX-33 and 8MB of RAM on it in there. It had VGA, a 124MB HDD, no sound card, and an Addonics VGA monitor and Kingspao enclosure. This was the first computer I had the internet on, and that's all I wanted it for at the time as internet access, and it was sthe only PC I wanted.....but other people....oh, they opened their closets.....
Main Computer July 2001 November 2002/November 2005 - 1995 IBM PC-330 100DX4 6571-W5K - a 100MHz 486 DX4 that started off with 8MB of RAM, 540MB HDD, and no L2 Cache, which was used by a Montgomery Alabama bank for awhile. My Room mate at the time gave me her old 5x86 133 and that had 256K L2 Cache in it so I moved the L2 to the IBM, and the Intel felt faster than the AMD, so I left the DX4 in there. I still ran this as a main and backup system well into 2005, and it was smy favorite 486, I still look for one like it when I can, though now they go for astronomically insane prices now. At it's strongest it dual boot Windows 98 SE and DOS 6.22/WFWG311 through the BIOS (you could switch boot order in the BIOS like a modern PC on this one), had 64MB of EDO ECC RAM, and had a total of about 20GB of HDD Space on it. It ran ANYTHING I threw at it and did so extremely well - Doom, no problem, Duke Nukem 3D, Great! Diablo - hell it's not even supposed to run on this thing and I got full frame rate and could play online (and did) over 56K Dialup on this computer. It even ran Postal with the Special Delivery expansion at one point (albeit with crap framerate, 1MB Cirrus Logic video was sjust not enough for it). If it had not died, I would still be using it to this day. I really ran the crap out of this old thing.
Main Computer November 2002 - March 2008 - GEM Computer Products 386 DX-20 upgraded to a Socket 7 Pentium, then later case modded into a Celeron 500, then a PIII 667, and lastly a PIII 1GHz with 1/2 a Gig of RAM (512MB). This computer pretty much ran as EVERY PC generation from 80386-Pentium III. I had to modify the backplane, the power swupply, and the case was cool as sfuck, but it was sort of my problem child in that it blew up hardware frequently, though that became much less of a problem during it's final years as a Pentium III. It started off Running DOS 6.21 and Windows 3.1, and then got upgraded to bigger IDE drives from a hardcard and a ST-412/506 Seagate 40MB MFM HDD and I started running Windows 98 SE on it, till the upgrade to 1GHz proved too unstable under Win98se, so I then went to Windows 2000 Professional SP3. This is the computer I started my YouTube Channel with, the computer I spent a lot of time building, hot-rodding, and modding. I used the ever-loving-crap out of it.
Main Computer March 2008 - June 2015 - In 2008 I was becoming friends with some colleagues, I guess. They kept making fun of my PIII in a 386 AT chassis, and started trying to get me to join them in modern gaming a bit, so I used my retro-skills to cobble together for $800 a pretty decent gaming rig locally sourcing most of the parts except the CPU. In the end, I had a system that lasted 8 years under mostly the same specs - 3.4GHz Pentium D, 4GB of RAM, NVIDIA 8800GT, and it ran Windows XP 32-bit at first, then got upgraded to Windows 7 x64, now it's my wife's computer and runs Windows 10 x64 9 years later and has no issues with that either.
Current Main Computer - December 2015 - present - I split my time these days between two Core 2 laptops - a Toshiba I got this past summer on a visit to some friends in Reno, and a HP G70 I found in the dumpster and repaired for dirt cheap using spares and parts from E-bay/RE-PC. Both run Windows 10 x64...but even then....one system now, I've been using MORE than those, all I ever use those for is web surfing, games, and bills......
My current 80486 DX2-66 actually gets more use than the Core 2's do. I'm always playing some game, chatting on IRC, and I've been looking into various smultitrack-recording options using the 486 (need to find a copy of Quartz AudioMaster Freeware and see how it does). Of course, the DX2-66 I have is a beast of a machine, it has 28GB of Disk space total through various DDO/Hardware tricks. It's not that slow, actually it runs Duke Nukem 3D, NES Emulation, ESNES, and Retro City Rampage 486 decently enough without too much frame rate drop. However, I'm still upgrading it. Iv'e been tempted to do what that one blogger did and take the REAL Windows 3.1x for a month challenge - I'm sure I could outdo him in productivity - maybe even circles. I do have my gmail setup on that computer and it works great albeit a little slow. I can also burn CDs (CDROAST !!!).