Yeah I know some games don't like FAT32. None of the ones I wanna play it seems, though

Try making the primary partition FAT16 and the rest FAT32.

Hello Harry Potter, hello rasteri

thx 4 your comments!

I have now succeeded in installing MS-DOS 6.22 along with Win98SE on 32GB sd-card:

1. primary partition 1.90 GB FAT16 => MSDOS 6.22
2. external partition with the remaining 30GB:
3. logical partition 3.90 GB FAT32 => Win98SE
4. logical partition 26.10 GB FAT32 => some games

All partitions were made by the fdisk from the Win98SE cd-rom.
MSDOS 6.22 installed from a cd-rom, I prepaired with the ISO image you can find online "DOS622_Install_CD_by_Looka_Bootable_EX.iso"

Advantages:
1. I can use Phils tweaks for a MS-DOS boot menu with or without EMS, XMS, CDROM etc. => good for games like U7, Falcon 3.0, Wing Commander 1, Turrican 2 etc.
2. I can boot independently into Win98SE and play early 90s Windows games
3. I can boot from Win98SE into DOS 7.1 and play for instance Doom1, Quake1 if I feel the need to do so as DOS 6.22 is only for very old or speed sensitive games

Hardware:
Asus P5A
AMD K6-3 / 400
Spea Mirage V7 2MB Trio64 PCI
Canopus 3dfx 6MB V1 PCI
64 MB SDRAM
SD2IDE adapter along with 32GB sd-card
SATA2IDE adapter along with LG H24N DVD burner
Creative SB AWE64 value
Onboard Solo-1 sound chip
Cherry PS/2 keyboard
Mouse PS/2
Gravis GamePad
MS-DOS6.22 & Win98SE

What I appreciate is, that I can slow down the machine to 486 level using SetMul or disabling 1st and 2nd level cache in bios.

I will probably never install an AGP graphics card, as it wouldn’t be worth it, since I already have a second and a third retro PC, and the Trio64 chip is one of these with the best DOS compatibility.