System(s) Specifications

JST-ESPER (the Precision)

Machine: Dell Precision 7750.
PSU: Dell 230W brick. 'Brick' is right -- you could build a wall out of these.
CPU: Intel Core i7-10850H.
RAM: 32GB DDR4-3200 CL22 @ 2933. It has 4 SODIMM slots, but populating them all shunts the RAM to 2133. Even with 2, it runs the sticks at 2933.
GPU: Quadro RTX 5000 16GB.
SSD: MSI Spatium M470 2TB.
ODD: External USB BD-ROM drive.
Other goodies: Intel AX211 cnvio WiFi.

OS: Windows 11 IoT LTSC 2024.

JST- (the T42)

Machine: IBM ThinkPad T42.
CPU: Intel Pentium M 735, 1.7GHz, 2MB L2.
RAM: 2GB DDR-333.
GPU: ATi Mobility Radeon 9600 64MB. To be as safe as possible with the RoHS issue, I underclock it to 225/200. It doesn't really cut performance by that much since the memory bus is so narrow anyway, it just cuts heat output, really. I swapped the 1400x1050 screen for the 1024x768 model as it's actually closer to what it can run games at, and at 14" is what I can actually read.
SSD: 256GB m.2 SATA on m.2 to mobile IDE adapter.
ODD: UltraBay DVD-ROM drive.
Other goodies: Ralink 802.11N mini-PCI WiFi.

OS: Windows XP SP3.

JST-ITHAENC (the Evo)

Machine: Compaq Evo N410c.
CPU: Intel Pentium III-M 1200MHz.
RAM: 1GB PC133. That i830M chipset is coming in clutch.
GPU: ATi Mobility Radeon M6. Kneecapped with only 16MB of VRAM and a stock clock of 143/143. It does 183/220 without much issue aside from heat -- I daily a clock of 167/183. Essentially a mobile version of the Radeon 7000, with only one pipeline and no hardware transform and lighting. That said, I'm shocked this has a "real GPU" at all -- it uses the i830M chipset, which has integrated Extreme Graphics. I suspect it has something to do with the native composite output this has, which would have been a killer feature for boardroom presentations in an era where it wasn't uncommon to have TVs on roller carts.
SSD: 128GB mSATA on mSATA to mobile IDE adapter.
Other goodies: Linksys draft-N PCMCIA WiFi card.

OS: Windows XP SP3. I really needed it for the better wireless support and the ability to run OpenVPN with working ciphers for my LAN.

JST-CRAGSTONE (also referred to as the 486, 386 on stilts, et al.)

Case: Some chinesium ATX desktop clone. It also happened to have mount points on the motherboard tray for an AT motherboard. I had to modify a blank ATX IO shield with a hole for the AT keyboard port and swap the momentary power switch for a toggle. I also had to modify one of the side "lips" on the lid because the tolerances on this board were so tight I couldn't close the case otherwise!
PSU: SeaSonic SS-350ET. The 5V rail is a tad low at only 20A, so I wouldn't trust it with a Socket A board, but here it does just fine. The lack of -5V doesn't bother this board, either.
Motherboard: Alaris Cougar. Interesting that it's IBM manufactured and doesn't make a single reference to the PS/2 standard... Strange little 486 board that also has a 387 FPU socket since the CPU is 386-derived. The MR-BIOS is also interesting. 7xISA-16, 2xVLB, but curiously the super-IO is onboard and it's fantastic -- the IDE is local-bus, the parallel port supports ECP I believe, and both COM ports are using 16550A UARTs. 256K L2 cache, 12ns chips. I modified my MR-BIOS with help from a friend to stop the CPU from being forced to a 3x multiplier so I could overclock the system bus to 33MHz.
CPU: IBM 486 "Blue Lightning", BL3-75 at 2*33 for 66MHz. A little background: IBM's agreement with Intel back in the day was that they could manufacture licensed Intel parts or modify them how they saw fit, but they could only sell them as part of a computer or major assembly like a motherboard, or as they'd call it, a "planar." The IBM branded CPUs you could actually buy loose were Cyrix parts manufactured and sold under license from them. An interesting design: they borrow from the 486SLC they loved to use in their PS/2s to give them "486" parts but keep the boards cheap. This, however, is fully 32-bit. It did inherit its cache control logic from the SLC though, so it can only cache 16MB of RAM -- problematic to say the least for use under Windows 9x. It's clock tripled by default and can understand i486 instructions but it behaves much like a 386 in other ways (and has a 387 FPU socket, as mentioned earlier). I gained more from overclocking the system bus than I lost from underclocking the CPU, so it's staying like this. FPU is an IIT 4C87-DLC40 at 33MHz.
RAM: 1x16MB FPM 72-pin SIMM. Windows 9x fills in the memory map top-down, so with any more than that it's running mostly uncached which is a big problem.
GPU: Cirrus Logic GD-5428 2MB VLB. A much more sensible, compatible choice for this machine -- the drivers for everything blessedly work and I have no complaints. This machine's CPU is slow enough that I really don't notice much of a performance drop from the S3 card I had before -- that's mercifully been retired to being a display piece, itself.
SSD/HDD: 2GB SD card in an SD to IDE adapter on the onboard local-bus IDE.
ODD:: Lite-On LTD-163D. It's beige, can read any CD I throw at it and any DVD too which comes in handy for data DVDs, has analog playback with a headphone jack and play/pause and stop/eject buttons. I can't ask for more really. It lives on an ISA secondary IDE card, as the onboard local-bus IDE doesn't like ATAPI drives unsurprisingly. That was really hit or miss back in the day to the point that stuff that worked that way was the exception rather than the rule.
Other goodies: CT2800 Vibra16S for sound. It has a real OPL3, and supports being initialized using DIAGNOSE and the BLASTER variable. I can't ask for more -- it's basically just an SB16. 3C-509B for LAN, disabled XT-IDE 386+ ROM in the socket as the onboard BIOS handles drives of this capacity fine and NT likes to freak out with the ROM putting the IDE controller into int13h mode with no specific driver. 1.44MB 3.5" floppy drive A:, 1.2MB 5.25" floppy drive B:. AVA-1502E ISA SCSI card, only an external 25-pin port -- no internal header or boot ROM. This connects to an external SCSI Jaz drive.

OS: Windows 95C. It boots and primarily lives in DOS, but networking is generally easier and more reliable under Windows, and there is a small cross-section of software that requires a Win32-capable OS and runs acceptably on a 486-class machine. Despite my having previously stated the opposite, on here with only 16MB of RAM and a slow 386-derived CPU 95 is definitely quicker. I modified this install using Nathan Lineback's instructions ons on ToastyTech to remove both IE3 and 4 from the setup files, but I installed IE5.5SP2 both for the runtimes and because that version has the best balance of features to speed on this hardware.

JST-SHOUSHI (Nostalgia Express)

Base Unit: Dell Dimension 9200. A bit of a stretched version of the E510 platform that I had as a child shortly before my Inspiron 530.
PSU: OEM Delta(?) supply. Those things had to power Pentium Ds. I completely trust it in this application, and I'm not stressing it either.
Motherboard: Dell CT017. P965 chipset, from what I understand it has either a 3 or 4-phase VRM. The way I see it, this was rated to handle Pentium Ds -- I could do my worst with the QX6700 and it wouldn't even sneeze at it.
CPU: Intel Core 2 Extreme QX6700. The OEM board sees it as a Q6700, but it does clock fine in software using ThrottleStop.
RAM: 4x2GB DDR2-800 CL5.
GPU: Quadro K2200. Needed Maxwell for competent Vulkan support.
SSD: TeamGroup T-FORCE 1TB SATA.
ODD: Generic black-bezel DVD+-RW. Does the job, looks alright doing it. Nothing special.
Other goodies: Onboard gigabit Intel LAN! SB0730 X-Fi XtremeGamer, DanielK drivers under Win7. 1.44MB 3.5" floppy drive A:, a strange choice for a 2007 computer, and a 3.5" internal USB card reader.

OS: Windows XP Pro SP3 (PAE patched)/Windows 7 Pro x64 dual-boot.

JST-KARA (da Geode)

Case: Some CoolerMaster Elite thing. Very plasticky and gross but it's what I had on hand.
PSU: Antec 350W unit -- 35A on the +5v rail, very important seeing how this doesn't derive CPU power from a +12v connector.
Motherboard: ECS K7S5A Pro. I have mine modified with the honeyx modded BIOS.
CPU: AMD Geode NX 1750 @ 1500MHz. Essentially a very heavily binned Thoroughbred-core Athlon XP.
RAM: 1GB (2x512MB) DDR-400 running at DDR-286, 143FSB, 2-3-2-6-8.
GPU: GeForce4 Ti4200 128MB. I must have a golden sample or something, because this thing clocks like a mother. It'll easily do Ti4400 clocks and come very close to Ti4600 clocks. This much with a passive heatsink that I cool with a 120mm fan bracket in front of the card.
SSD/HDD: 256GB SATA SSD on StarTech SATA->IDE adapter.
ODD: Generic IDE DVD+-RW drive. Does the job. Nondescript.
Other goodies: 1.44MB 3.5" floppy drive A:. Intel PRO/1000GT NIC. AU8830 Aureal Vortex 2.

OS: Windows XP SP3. It's just what makes the most sense on there.

JST-ADVOCATE (Proxmox host)

Case: Fractal Define R5. Much more convenient for swapping in hard drives.
PSU: EVGA 750G5. Superflower OEM, very solid.
Motherboard: ASUS ROG Maximus Hero VIII, UEFI modded with CoffeeTime.
CPU: Intel QTJ1 engineering sample. Essentially an i9-9900HK. Shows "GenuineIntel CPU 0000" as its CPUID.
RAM: 64GB DDR4-3200 (2x32GB), clocked to .
GPU: Intel UHD630 integrated, passed through to NAS VM for Jellyfin transcoding.
Storage: 1TB NVME SSD for booting, VM storage. 3x8TB WD Blue for mdadm software RAID5. Open hotswap bay for backup operations.
Other goodies: Inspur Intel X540 10GbE NIC, Thermalright 240mm AIO, SATA hotswap bay for backups.

OS: Various; Proxmox VE host.