Ok, so I have built a computer from parts. Maybe several, but who's counting.
My current PC(s):
Primary System
* AMD K6-III/400 CPU @ 450=100x4.5 (2.2V) ($75)
* Cooler Master DP5-5021B fan (20-35W, 9.2 CFM, 0.61 oC/W, 5000 RPM, 29 dBA) ($6.75)
* FIC VA503+ motherboard (MVP3, 1024k, 124MHz) ($69)
* 128MB + 64MB CAS-2 Acer SDRAM ($? + $48/2, used)
* Diamond Fireport 40 Dual UW SCSI controller (ultra fast/wide) ($41 used)
* Quantum Atlas V 18.3G 7200RPM USCSI-U2W LVD HDD (29MB/s peak, very quiet) ($163.75)
* a second Quantum/Maxtor Atlas V 9.1 G LVD SCSI HDD ($85?)
* a third Quantum/Maxtor Atlas V 9.1 G LVD SCSI HDD ($1 used)
* HP 8/4/32 SCSI CD-RW ($22 used)
* Conner CTMS3200 2G/4G SCSI tape drive (410K/s sustained) ($140 closeout)
* HP SureStore 6000i DDS-2 DAT drive ($31 used)
* Sound Blaster 16 ISA, jumpered, w/ SCSI-2 ($16 used)
* Wave Blaster hardware wavetable daughtercard ($15 closeout)
* Matrox Millennium II 4M PCI (MGA, 50ns WRAM) ($43 used), with
* 12MB memory upgrade for Millennium II ($20 surplus)
* Dell flat-screen monitor (17" Trinitron, .25mm aperture grille) ($0 used)
* US Robotics Courier external V.Everything modem (V.34) ($25 used)
* 10mbps PCI Ethernet, Realtek 8029 ($13)
* 100mbps PCI Ethernet, SMC 9332BDT ($1 used)
* Older mid-tower, 250W, two fans, 3 x 5.25", 2+3 x 3.5", numeric LED (reads 166 :-) ($75)
* Replacement AT power supply for case ($20), with replacement 8cm fan ($3.50)
* Two thermal-control ball-bearing 8cm case fans ($6.50 each)
* TEAC 3.5" 1.44M floppy ($?)
* Quimax 84-key PC keyboard (really great, short-travel light-click keys) ($0 used)
* Mitsumi PS/2 mouse ($6.50) - a delightful little beast, much nicer than the klunky Mouse Systems it replaced. A close imitation of the Microsoft Basic Mouse.
Secondary System
* AMD Duron-750 CPU ($42 new; the least expensive Duron, but overclocks well)
* Thermaltake Volcano 7 cooler (variable speed fan) ($17)
* Gigabyte 7iXE4 ATX motherboard ($66; 2 ISA or 5 PCI, 1 AGP)
* 64+64MB CAS3 Compaq SDRAM (stable at CAS2; $53 used)
* Matrox Millennium II AGP video card, 4MB ($7.50 used)
* ADI 5G (17", .26) ($300)
* Seagate 30GB IDE Barracuda disk ($53 new; very very quiet)
* Sound Crown (Ensoniq) SC-1370 AudioPCI audio ($10)
* Sony 1.44 FDD ($22/3 used)
* Plextor 10/12/32 IDE CD-RW ($20 NOS)
* Mouse Systems 104-key AT keyboard ($20) (Scam Alert: they don't send the mail-in rebate)
* Mitsumi 3.5" 1.44M floppy ($?)
* Mitsumi PS/2 mouse ($4.50)
* 43 CFM slot system cooler ($11)
* thermally controlled ball-bearing case fan ($6.50)
* Zoom 56Ki internal faxmodem ($80)
* SMC 7332BST 100baseT network card ($4/4 used)
* In-Win H500 250W Desktop ATX case ($47 + $20 ship) (w/ FSP235-60 power supply; "with noise killer")
Upgraded Work System
* AMD Athlon XP Mobile 2400+ (1.45V unlocked) (1600MHz, stable @2200MHz @1.5V; $78)
* AMD thin-fin heat sink w/ 6cm magnetic bearing fan (swapped dead fan) ($0 used + $6)
* Shuttle AN35N motherboard (nForce2 ultra, dual-channel, w/ audio & video) ($60)
* OCZ 256MB cas2 ddr pc3200 sdram (2-2-3-6 at 200MHz, 2-2-2-5 @166, 2.5-3-3-11 @230) ($61)
* Aopen GeForce4 mx440 video card (AGP 8X, 64MB DDR; $40)
* Seagate Scorpion DDS-3 DAT tape (720k sustained w/ compression off; $58 used)
* Maxtor Atlas 10k III, 18GB (55MB/sec peak, very quiet; $28 used)
* Yamaha 8424 CAV SCSI CD-RW (1.8-3.6MB/s) ($232)
* Tekram DC-390U2W SCSI controller (sym53c895+sym53c141, ultra2/ultra/fast/wide+ultra/wide) ($161)
* Plextor 12X caddy SCSI CD-ROM ($25/a used)
* Thermal-control ball-bearing 8cm supplemental case fan ($6.50)
* NMB-II 102-key keyboard (nice, but has 3-key rollover bug) ($40)
* Teac 1.44 MB floppy drive ($12)
* Integral Technology FlashBus video capture board (borrowed)
* Conner CTMS3200 2G/4G SCSI tape drive (410K/s sustained) ($28 used)
* Hitachi CM715-U 19" monitor, running at 1280x1024 and 1440x1080. Would be a very very nice monitor if not for the out-of-focus area in the middle of the screen ($286)
* Microsoft Basic Mouse (or a knockoff; I wanted the serial option) ($7.50)
* In-Win S500 mid-tower 235W ATX case ($30 auction, + $19 shipping)
* Sparkle/FSP 350W power supply ($47; w/ slower/quieter fan) (the fan in the original 235W power supply started to get noisy, thus the upgrade)
Parts left over, as of 2004-08-03
* AMD Athlon Thunderbird 700 MHz Slot-A cpu (1.7V, running @ 825) ($167)
* Golden Fingers Slot-A Athlon clock/voltage adjust device ($23)
* Thermaltake Golden Orb Athlon cooler (26 dBA, 20 CFM, .32 oC/W) ($21)
* Gigabyte 7IXE ATX Slot-A motherboard (2 ISA or 5 PCI, 1 AGP) ($103)
* 128MB + 128MB + 64MB CAS2 PC100 SDRAM ($15 + $15 used, $99)
* Quantum Atlas 10k II 9.1G 10000RPM USCSI-U2W LVD HDD (41MB/s peak, very quiet) ($167)
* SMC 7332BST 100mbps PCI Ethernet ($4/4 used)
* Sound Blaster 16 ISA, w/ SCSI 2, jumpered ($? used)
* Matrox Millennium II 4M AGP (MGA, WRAM) ($27 used), with
* 4MB memory upgrade for Millennium II ($0)
Parts not yet used
* TR2-M1 heat sink w/ 8cm cooling fan (quiet; $13)
* Adaptec 39160 dual LVD-160 controller ($50 used)
* Maxtor Atlas 10k III, 18GB ($13 used)
* Seagate 20GB IDE 7200 RPM Barracuda ($22 used)
Legacy System(s)
Obsoleted Secondary System
* AMD K6-200 CPU @ 225=75x3 (rev. C-9736; stable up to 250MHz) ($210)
* Cooler Master TI5-601525 fan (28W, 19.8 CFM, 0.7 oC/W, 4400 RPM, 31.5 dBA) ($7.50) - nice fan, but is the loudest component in the case
* FIC PA-2007 motherboard (VP2, 512k 2-1-1-1, 75MHz) ($97)
* 32MB Hitachi + 16MB Micron 60ns EDO (work at 50ns) ($110 new + $20 used)
* Diamond Fireport 40 UW SCSI controller (ncr875aj, ultra fast/wide) ($43 used)
* IBM DDRS 34560 4.5G 7200RPM SCSI-U.Wide HDD (13MB/s peak) ($86 used)
* Toshiba 4X SCSI CD-ROM ($12 used)
* Jaton 58P 2.25 MB (ET6000, MDRAM; 132x60 very fast text) ($47)
* In-Win A500 AT desktop case ($30 used)

As Parts
* AMD 486 DX2/66 3.3V ($0 used)
* Cyrix S-40 (40 MHz 486, 2K cache) ($120)
* 3-VLB 486 motherboard, compatible w/ CxS-40 ($120)
* 8MB of 1M x 8 FPM 30-pin SIMMs
* WDC Caviar 540MB IDE HDD (3.5MB/s peak) ($345?)
* Quantum QFB1280A 1.28G 5400RPM EIDE HDD (6MB/s peak) ($265)
* Quantum Fireball EX 6.4GB IDE hard disk ($160 used; loud)
* Mitsumi 2X CD-ROM (proprietary controller :-) ($128)
* Mozart MAD SB clone ($68)
* Genoa Phantom 32i VLB (Tseng w32p chip) ($185)
* 10mbps ISA Ethernet ($28)
* Zoom Telephonics 14.4 external box modem, with lots of lights :-) ($250-ish)
* TEAC 5.25" 1.2M floppy ($?)
* Desktop AT case ($0 used)
* Mini-tower AT case ($45) - thin piece of junk, but my power supply died and I was desperate
Parts is Parts

PROCESSORS and MEMORY
* AMD K6-2/350 CPU @ 372=124x3 (rev. A-9839) ($131) - breaking down, will not clock faster than 336 any more, but it sure has lived a glorious life. This chip has served faithfully and well, and I grieve its passing.
* AMD K6-2/450 2.1V mobile processor ($0 used; replaced w/ K6-2+/550, $75)
* AMD K6-2/433 2.1V mobile processor (used, w/ $165 Presario mb)
* Cyrix PR-300 (233) 2.9V Socket-5 pentium-clone processor ($0 used)
* Cyrix PR-233 (166) 2.9V Socket-5 pentium-clone processor ($0 used)
* A number of 486, Pentium and K6 cpu coolers from Birchtek, Cooler Master, KWI, as well as several unbranded ones. I always am on the lookout for a quieter fan or better heatsink, and the fans do start to get loud after a year of use as they wear (yes, these are ball bearing fans, but they don't seem to like being on their side in a tower case).
* generic ball-bearing CPU fan, ?5000 rpm, ?29dBA ($4.25)
* Speeze socket A cooler ($12), with 60x25 mm replacement fan
* 64MB CAS2 SDRAM ($48/2 used)

STORAGE
* IBM DDRS 34560 4.5G 7200RPM SCSI-U.Wide HDD (13MB/s peak) ($257)
* Quantum Atlas II 2.27G 7200RPM SCSI-UW HDD (9.4MB/s peak) ($172)
* Micropolis 4.3GB Tomahawk 4345 SCSI-wide (in the external case) ($36 used)
* Archive 150M SCSI tape drive (in external case) ($0 used)
* External SCSI case for one full-height 5.25" and one half-height 5.25" device ($0)
* External 50-pin Centronics active SCSI terminator ($2.50)
* Internal-50 to external-25 pin SCSI cable adapter ($6)
* SCA-80 to 68-wide and 50-narrow SCSI adapter, with termination ($13 auction)
* SCSI-wide (68-pin) device to SCSI-narrow (50-pin) cable adapter ($11)
* Quantum Atlas II 4.5G SCSI 80-pin SCA HDD ($8 used)
* Diamond Fireport 40 UW SCSI controller ($25/a used)
* Diamond Fireport 40 UW SCSI controller ($? used)
* Tekram DC390F UW SCSI controller ($6/3 used)
* Tyan Yorktown (s1365) SCSI controller (ncr825a, fast/wide) (drivers) ($75)
* TEAC CD-ROM
* Sony SDT5000 DDS-2 DAT drive in external SCSI case ($0 used, repaired)
* Archive Python DDS-1 DAT drive in external SCSI case ($1 used)
* Archive Python DDS-2 DAT drive mechanism ($?? used)
* HP SureStore 6000i DDS-2 DAT drive ($1 used)
* Maxtor Diamond Max Plus 30GB 7200 RPM EIDE HDD ($0 used, bad sectors and getting loud)

VIDEO
* #9 FX771 PCI video card (S3-968, 2MB VRAM) ($270)
* Mitsubishi Diamond Pro 17TX (17", DiamondTron; .25mm aperture grille) ($1050)
* Gateway 17" monitor ($0 used)
* Smile (aka. KFC) 15" monitor (poor quality) ($265) (h-pos too left)
* Sound Crown (Ensoniq) SC-1370 AudioPCI audio ($10) - a spare

INPUT/OUTPUT
* SMC 10mbps ISA Ethernet ($6 used)
* SMC 7332BST 10/100T 100mbps Ethernet cards ($4/4 used)
* Microsoft J-Mouse ($0 used) (too large for my hands; I liked the old, smaller model better)
* PS/2 keyboard, AT keyboard adapter ($6)
* US Robotics Courier external V.Everything I-Modem ($43 used)
* Practical Peripherals 28.8 external faxmodem ($285)

UNRELIABLE
* 32MB RAMS 60ns EDO (flaky at all settings!) ($0) - given to me because the owner thought the memory was junk. On testing it, I have to agree, this memory is not stable under any of the settings possible on the motherboard, including the slowest and most conservative timings.
* Toshiba 12X CLV SCSI CD-ROM (1.8MB/s) ($92, does not detect)
* Conner CTMS3200 2G/4G SCSI tape drive (used; does not detect tape)
* Conner CTMS3200 2G/4G SCSI tape drive (NOS; does not detect tape) ($25)
* Conner CTM3200 2G/4G IDE tape drive (dead, fried w/ experiment) ($0 used)
* Plextor 4X caddy SCSI CD-ROM ($6.50 used; intermittent read errors)
* Sony SDT5200 DDS-1 DAT drive (keeps stopping during read) ($0 used)

Updated 10/17/97, 10/20, 11/12, 3/23/98, 5/29, 7/17, 11/26, 12/06, 10/10/99, 10/21, 01/20/00, 7/16, 8/15, 9/7, 06/23/01, 4/3/2004, 8/3.