Something nobody here will ever admit is that you can get 99 percent of the fun with like 10 percent of the work. If I actually played games as opposed to building absolutely unhinged "perfect for *insert activity*" builds, I'd legit throw a GeForce 6600 PCIe onto a late LGA775 board (mostly for the solid state caps that came into common usage around that time) with an LGA775 Pentium 4 with a modern SATA optical drive and a modern SATA SSD. You could probably put this build together for $100~ and it would run nearly every game made from 1995 to 2005 flawlessly and it would be extremely reliable. For monitors any late 1280x1024 LCD would be my recommendation, CRTs are getting kind of pricy and they are a nightmare to keep adjusted correctly.
The old super high end hardware is all unreliable as shit now. Old high end GPUs drop dead for absolutely no obvious reason, old hard drives die constantly (often right after you finish setting up the OS....), old motherboards are suffering from cold solder joints and bad caps, etc. I only recommend investing in the "good stuff" if you intend to learn electronics to a sufficient degree to repair and maintain your own stuff. The mid end stuff on the other hand, that didn't leave the factory running balls to the walls with extremely complex circuit designs are still mostly doing well. Like seriously whatever high end part your looking at, just look at the next gen immediately after its mid range stuff. its the same tech but usually simplified.
I honestly have no idea keeps me interested in this hobby, 3/4ths of my time is just testing new acquisitions and chasing down various maintenance issues trying to keep the current fleet in good order (which is quickly becoming a problem, I'm almost certainly going to have to learn to let go and pass some of this stuff onto new hands at some point). I'm also slowly starting to make concessions to the march of time, like I'm trying to move fully away from mechanical hard drives for my actual builds over to either SATA SSDs for the systems new enough to have SATA or IDE-to-SD adapters for the older systems. I'm also trying to move away from physical discs and relying on disc images in as many places as possible.
Bought more GPUs. Since I've noticed PCI bus GPUs are going nuts for some reason I'm trying to grab whatever ones I don't have that I am sure I want. Right now I've got an X1300 PCI ($18) and a Trident Blade3D 9880 PCI ($20) in the mail, along with a Radeon HD2600XT AGP (which is a rare DX10 class AGP card. Paid $40, not great not horrible. You don't see the HD 2000 AGP cards very often anymore). Still a few more expensive models I feel like I NEED in my collection. I'm mostly going after very fast (considering the bus they are connected to) cards like the X1300 or cards that are niche/unique like the Blade3D. I already have PCI examples of TNT2, GF2MX, GF4 MX, GF5200, GF5500, and Radeon 7000. I think I have a Radeon 9000 PCI somewhere too (though its not listed in my spreadsheet).
I also bought a lot of 22 as is non working GPUs for $40 and sort of burned myself. They were all low end/entry level AGP cards and in my hubris I assumed the previous owner was incompetent and didn't test them right since these low end GPUs almost never die in my experience. I figured probably half of them would work with little to no effort.. Nope, all but 3 so far are actually dead. Going to slowly go through them and see if I can identify the issues with them. Out of the 3 that worked 1 just worked with no extra work, and of the other 2 one I just cleaned the AGP pins with a rubber eraser which did the trick, and the other just has an intermittent cold solder joint in its VGA port which I can fix whenever I get around to needing a GF2MX/200 16MB for something. Several of the others went from no display to artifacting after I cleaned the AGP pins, so that suggests I will get more of them working.
I also grabbed a Dell Precision T3500 at the local thrift store for $5. Had a quad core Nahelem 1366 Xeon in it, 6GB of RAM, a Quadro FX 580, and a PCIe Soundblaster X-Fi. This thing actually got me thinking. My first retro machine that I actually bought (which excludes the two prior machines I was given for free. A Deskpro EN and a DEC Celebris I immediately damaged due to being a complete noob about handling retro hardware) was a Dell Dimension 4600 in like 2016. In 2016 that Dell was 12 years old. I happily considered that retro, and that machine was obsolete to the point of complete uselessness by then. This Precision T3500 is currently 13 years old... is it retro? I could certainly use it as an XP machine, but I could also put an SSD in it and have a completely useable office PC.