I recently purchased a Thinkpad R50E. Pentium M 1,6 GHz, 1,25 GB RAM, It was running Windows XP with the pre-installed IBM (I assume) bloat.
It has a dead CMOS (bought a replacement, it's on its way, I have to replace it because the BIOS default changes the IRQ of some PCI things to 11, rather than autoselect, which is not good?), it came with a charger, the battery health is at 100 % in BatteryInfoView (sweet) and it cost me just 30 € (shipping included).

I liked Windows XP back in the day, but for XP things, games up to 2010 let's say. Certainly not backwards compatibility with DOS. And that's the era that I like the most, 90s DOS games.
The era before that, I'm not so fond of, because the games were too simplistic and I never liked the 4-color CGA or the 16-color EGA games, so I stuck with VGA, and the early 3D games aren't aging as well.
1991 to 1997 is that sweet spot, classics like Doom, Duke Nukem 3D, Blood, that's what I want to run.

So far, this is the list of things I've done to this machine:
1. Took out the 1 GB module that was also in the machine, taking it down from 1,25 GB to 256 MB, a much more reasonable amount for a DOS machine, still an overkill, but I'm not hunting down an old module for nothing
2. Installed Windows 98 SE so that I can restart in MS-DOS mode, if I choose to do so
3. Burned a USB driver from philscomputerlab to a CD and got USB working so that I can move stuff to and from the machine (it has no floppy drive, only a CD one)

But this is where 4. should be, and isn't. I got other things working... sort of. This machine was obviously never meant to use Windows 98, so there are some problems. Here's the list of "sort of" working things:
A) Audio - When I boot to Windows, the startup sound plays normally, I have a volume control in the bottom right, the physical buttons of the laptop work fine, but the SoundBlaster emulation... sound effects work, FM synth music does not. MIDI also doesn't work, it has a tab in the device manager thingy, but it's all greyd out, like there is no MIDI device.

It's a SoundMax... something, tried both the Windows 98 and 2000/XP drivers, there is a SoundBlaster emulation tab, you can turn it on and off, choose the address and IRQ, but it only emulates the sound effects? Is that normal?
And below that, there is an option for a MIDI address, it defaulted to 300 (shouldn't it be 330?), but I get nothing despite trying multiple devices in game settings (General Midi, Sound Canvas, Waveblaster).

B) Trackpoint - It doesn't have a trackpad, but rather, the red dot in the middle of the keyboard. The 2000/XP driver wouldn't install, requires a more modern OS, the Windows 98 "driver" is only accesibility, which... granted, it works, it's in the control panel, but it didn't give me control of the pointer. So I went into device manager and configured my Uknown Device to use a Standard PS/2 mouse driver, It shows a warning in the device manager, Windows actually said I have a virus and that performance might very (very weird), but the trackpoint works, and mouse buttons work, even in Doom.

C) Graphics - This is the most bizarre one for me. I got the Intel Extreme Graphics blue square in bottom right, I have an Intel Extreme thingy in the Control Panel, and yet I'm stuck with 640x480 and 16 colors, I don't understand this one at all. Graphics are absolutely fine in DOS games like Doom and Blood, no glitches, no slowdown, 256 colors showing perfectly.

So I don't know what to do next. I know people have tried to turn other Thinkpads into Windows 98 machines like the R51, saw a 40-minute video on that, it might not be possible with all of them.
I'm hoping to find someone with knowledge of this particular Thinkpad, because maybe it's just a slightly different version of another Thinkpad, and it might have good Windows 98 support. I know the R51 has a plastic twin brother or something like that. So, if you've experienced similar issues and can provide solutions, or if you have some ideas I should try, please, let me know. Thank you in advance.

EDIT:
Got the sound working with a SoundMax 3Com EuSynth older driver, General MIDI works for music (sounds a bit meh, but works, dammit) on address 300, SoundBlaster emulation still works at 220.
Formatted the hard drive because of bad drivers and the machine now automatically detects the trackpoint and it works without me doing anything (very weird).
Got the graphics working thanks to a Extreme Graphics driver from another machine, for another Thinkpad. They were made for Windows 98 SE, and it kinda works, sometimes I get a blue screen that I can just skip, and I have a nice 1024x768 desktop with all the colors. So pretty much everything I wanted to work... works. Sweet.