Try FreeDOS. It has far better support for modern systems, and its Fdisk & Format can get you Fat32 natively (not that you need it with 128MB.) You can even partition & format the drive with FreeDOS, reboot, and install MS-DOS, although FreeDOS works better on these types of machines IMHO.

This is my goto for thin clients, tells you a bit about it and how to install Win98 so dos is definitely doable.
https://www.parkytowers.me.uk/thin/wyse/vx0/

The 10 specifies its OS is a Wyse customized linux install, Fdisk doesn't understand linux partitions, so yeh just use something bit more powerful.

I actually did browse your website in the past but I did manage to get lucky in my own way.

I bought a brand new external ASUS CD/DVD-RW drive from best buy then I used another PC to download a floppy boot image from https://www.allbootdisks.com/download/dos.html and used a CD burning program (K3B for linux) to burn the CD. I know its insane, but the CD ends up having a boot image and no other files, so I'm limited to 1.4MB of storage which I am managing OK.

Then I end up going into the bios and figured out that I had to use the default password "firewire" to get in. Then I configure the boot sequence so it searches a USB based CD-ROM for a boot disk. It seems to work fine and I can setup the internal flash drive as a bootable drive.

One sad part is without changing any further bios settings, If I boot from the flash drive, I'd have to wait a few minutes while it searches for the bootable CD.

Sorry for the necro, but I just encountered this with a pair of Vx0 V10L units from eBay.
The previous post about the "L" denoting Linux was correct. The DOS 6.22 edition of FDISK has zero clue about those newfangled non-dos partitions, so it freaks out.

You can create a Win98SE boot "floppy" from any old USB drive and get rolling forward:

1. Prep it as a ZIP disk (Boot as ZIP) with 2000MB FAT16 partition with RMPrepUSB
2. Download and mod a 98 boot disk image to be 2.88MB with WinImage
3. Download Bret Johnson's USB driver and use HxC DosFloppyBrowser to add USBUHCIL.COM, USBHCIL.OVL, and USBDRIVE.COM to the floppy image
4. "Burn" the image to the USB drive with UNetbootin
5. Go into the Wyse BIOS (Fireport is the password if it's stock), go to Advanced BIOS Features, set the first boot device to USB-ZIP, second to HDD
6. Still in the BIOS, back up one level go into Integrated Peripherals, and set OnChip EHCI Controller to DISABLED (DOS don't play with that, like, at ALL)
7. Stick your freshly funky USB pretend ZIP drive in the front port, save changes (F10, Y) and reboot
8. Startup without CDROM support (faster boot time and redundant to scan for a CDROM drive right now anyway)
9. Once you're at a prompt, the FDISK version you have available will recognize the three non-DOS partitions, which you can delete and create your own new bootable DOS partition.
10. Reboot, get back to the prompt
11. A:/>format c: /s and you will have a bootable DOS environment, but no commands or tools yet.
12. A:\>mkdir C:\DOS
13. A:\>copy *.* C:\DOS
14. There's your initial DOS environment with all the core bits!
15. Pull out the thumb drive and reboot
16. Again at the prompt go into C:\DOS
17. C:/>USBUHCIL
18. Answer Y to continue. Consider this like the USB "framework" for DOS, like .NET in Windows. Part of its job is to force any USB drive trying to show up with its fancy EHCI or OHCI schema back to the O.G. UHCI. It's more compatible with a broader range of drives (I haven't found one it won't use yet), and while it's slower than modern USB2 or 3, it's waaaaay faster than old school floppy or CD!
19. Put a new thumb drive formatted as FAT32, up to 20GB in one of the back slots <--This is important, and I'm not sure why, but I suspect it has to do with the separate controller the front USB port is connected to, rather than the direct onboard connections in the back. Perhaps the controller accessed by the mobo USB header is incapable of falling back to UHCI? Like I said: I don't know why; I just know what works.
20. C:/>USBDRIVE

Now your thumb drive should be available as D:, and you can do as you like from there! You are running the Win98 DOS at this point, but it's the most compatible, and you can take advantage of the Windows 98SE driver support to have working hardware at the DOS prompt level too. This got me back into FastTracker II pretty nice! 😀

I have the detailed wherefores and howdoits with pictures and everything at https://weaselsworld.com/wyse-vx0-fattening-u … -a-thin-client/