Ok I got the MB, cpu, ram and video card in so I just tested to see if it would boot with the windows 98 easyboot usb and it seems to be working properly.
But dear god I was not expecting the cacophony when I first turned it on; it sounds like a wind tunnel. I don't have it in a case right now so maybe I could at least replace the CPU fan with a decent 120mm Noctua one but I'm not sure if just laying it on top of the heatsink is the best idea. Would it be less effective because of the lower RPM and less concentrated airflow over the heatsink?
edit:
got the SSD but not the IDE adapters so I tried just using the onboard sata to see if it would work. I already partitioned and formatted the drive in Linux and the installer seems to see the drive because I made the setup directory on it to copy the install files over. It copied about one file and then basically stalled so I guess it's not going to work. It also seemed to stall when I tried formatting it with the win98 installer instead of Linux.
The drive appears under the 3rd IDE master. I tried swapping it to the other set of sata ports but then it wasn't detected.
What was really strange was that a Linux install I made to a usb drive using the win98 system was not able to detect the sata drive. Dmesg reported some error and lsblk would not list the drive. I tried both AHCI mode and SATA mode. I mean, surely a modern linux distro still has sata2 support? So since Windows 10 would only format the drive as NTFS or exfat, I actually had to boot another linux install on my windows 10 machine and use that to format the drive.
update:
I've gotten it up and running now. I didn't know that you can only boot windows 98 on either the 1st or 2nd IDE channels and my motherboard doesn't seem to have an option to reassign the 3rd or 4th ones. I just went ahead and ditched the sata ports completely and got a sata to pata converter which seems to be working well so far. Compared to videos I've seen online with people using mechanical drives there's still a pretty huge boost in performance when using a SSD even though I guess it's severely bottle necked. I did have to use Linux to partition and format the drive otherwise scandisk came up with errors about LBA or something when I ran windows 98 setup.
Drivers from VIA failed to install but loaded upon reboot. There doesn't seem to be a 98 driver for my onboard ethernet, although I tried one which didn't work that was for a SiS chipset that used the same realtek model.
My magic-ns adapter works which is really nice because that means all modern controllers will work wirelessly.
Issues I've had so far:
Unreal gold runs like garbage for some reason. Enabling 32bit color slows everything to a crawl. I guess because it's a glide optimized game because when I used dgvoodoo it ran much better, about how it does on my modern machine. Without it there doesn't seem to be a way to vsync the game at all and the FPS fluctuates wildly.
Speaking of vsync, I tried adding the coolbits registry additions that's supposed to open up more options in the control panel but they don't show up for some reason. Using regedit I can see the new entries listed there but not in the control panel. Having more vsync options would be nice because using the default vsync profile setting for Unreal did nothing at all. Neither did enabling it in the game itself.
Need for speed 1 se had some crackling audio. I'm using the wdm driver for the Yamaha ymf 744 card because I need daemon tools working with cd audio so perhaps that's the cause? Also the fmvs have artifacts.
Super Bubsy completely crashes the system every time.
Mortal Kombat Trilogy's video mode detecting utility fails and I can't play the game. Using the dos version works but the colors are all messed up.
Bug!'s fmv videos are messed up but gameplay seemed okay. Crashed one time.
Last Bronx runs too fast.
NFS3 and High Stakes have inexplicable suttering/slow downs but that also happens on my modern pc with fan patches. I think they run at some odd refresh rate.
Daytona USA CE runs pretty well.
TL DR
So all in all I guess I had pretty much an authentic win 98 experience even after trying very hard not to have one.