Certain AT power supplies are worth repairing. There's not much point in keeping the cheapies.

What usually fails on them?

Capacitors are getting dry. And Supply will run out of spec. Eg. Ripple destroying your lovly 486 Mainboard.

Example of old capacitor:

another one from nicetux:

when capacitors become resistors..

every old power supply should measured before use.

eevblog:
https://www.youtube.com/watch?v=Edel3eduRj4

^^^ This guy Agilents 😉

99% of the time, any PSU failure I've had in the 90s and early 2000s on AT systems was a fuse. Once a transformer let out.

ATX though...

fitzpatr wrote:

To me, period correctness only matters so far as compatibility is concerned. For example, someone on here recently had a thread where they were using an Asus P5A (Super7, 1998) with a Pentium 233MMX (1997), and Windows 3.1 (1993). As I had pointed out in that thread, a 5 year hardware and software gap in those days is quite significant, would not get the most out of the hardware (a concern when ATX Super7 boards are rare, or at least expensive), and could lead to driver troubles and other quirks.

As far as that combination goes, the Pentium MMX was targeted as a low-end processor in 1998/early-1999, so I'm sure someone would've built a budget P1 build with an ASUS P5A motherboard BITD. As far as Windows 3.1x is concerned: Sure, it may seem a little overkill to run just Windows 3.1x on a Pentium MMX machine, but for someone who wants to skip 486 hardware, a Pentium build (with or without MMX) with compatible hardware makes a fine multi-booter for DOS/WFW3.11, Windows NT 3.51/4.0, and Windows 95/98. I've been careful with picking hardware for my build by making sure I ended up with video, network, and sound cards with drivers for the designated OSes (in my case: MS-DOS 6.22 w/ WFW 3.11 and Windows NT 3.51).

fitzpatr wrote:

There is no reason other than nostalgia to artificially limit your choices. I would not use an older power supply or fan, but I would use an old Hard Drive for that wonderful whirring sound!

I agree with you there. CF cards and SSDs are great and all, but I still quite enjoy the sound of an old hard drive. You've reminded me that I have a couple systems that are in need of a fan replacement.

KCompRoom2000 wrote:

As far as that combination goes, the Pentium MMX was targeted as a low-end processor in 1998/early-1999, so I'm sure someone would've built a budget P1 build with an ASUS P5A motherboard BITD. As far as Windows 3.1x is concerned: Sure, it may seem a little overkill to run just Windows 3.1x on a Pentium MMX machine, but for someone who wants to skip 486 hardware, a Pentium build (with or without MMX) with compatible hardware makes a fine multi-booter for DOS/WFW3.11, Windows NT 3.51/4.0, and Windows 95/98. I've been careful with picking hardware for my build by making sure I ended up with video, network, and sound cards with drivers for the designated OSes (in my case: MS-DOS 6.22 w/ WFW 3.11 and Windows NT 3.51).

I'm all for people doing this hobby in whatever way makes sense for them! I'd argue that one could also use a K6-3+ and vary the multiplier through software to expand the effective range of speeds, but at no cost to compatibility. The board is the expensive part, anyways. It's up to the builder to research thoroughly to avoid having a build that is incapable of performing the intended tasks.

When I try to stay period correct in a build, my scope is limited to the Mainboard/CPU/Graphics. The rest, I see as conveniece. Things like optical/hard drive, power supply, cooling etc are not really my interest. Strictly speaking even maxing out the RAM is often not period correct - who had 512MB RAM in 1998?

I go with the if you might have upgraded to this, which opens alot of doors for me for XP era systems, because I was a highschool kid in the begining and working fastfood until 2008, I upgraded in a way no one else would, like a Sempron 2800 AM2 paired with an 8800GS 🤣

appiah4 wrote:

When I try to stay period correct in a build, my scope is limited to the Mainboard/CPU/Graphics. The rest, I see as conveniece. Things like optical/hard drive, power supply, cooling etc are not really my interest. Strictly speaking even maxing out the RAM is often not period correct - who had 512MB RAM in 1998?

My 486DLC circa 1992 currently counts 32Mb RAM installed. Total overkill.

My P133 has that much. It could have had 64 but I stopped at something that was more representative of tue era. Mu DX2 has 8MB and U5SX33 has 4. Why? No good reason. You can go overboard with these convenience upgrades as you please IMO.

appiah4 wrote:

My P133 has that much. It could have had 64 but I stopped at something that was more representative of tue era. Mu DX2 has 8MB and U5SX33 has 4. Why? No good reason. You can go overboard with these convenience upgrades as you please IMO.

Thats why I put 256mb of ram in my pentium 1 board, 4x64mb 72pin SIMM's

As long as your chipset can cache that, why not?

I think period correct build is good for those when you want to replicate a pc that you used to have. Of course for most people changing parts that don't change the experience of using the pc like power supply or cooling don't matter that much.