China DOS Union

For example, can it start up the sound card, graphics card, and so on?
Actually, I want to make a complete system on a USB flash drive. USB drives are a few GB, and back when I was in school, a computer hard drive was only 4.3GB.
That way, I could just plug in the USB drive to replace my current hard drive.
In theory, that should be possible, right?

Which system do you want to run?

Of course I'd start with the simplest one, DOS.
Because I think the name DOS looks like the kind of thing that should be able to run.
disk operating system...
A USB flash drive, isn't that just a U disk?
If DOS can run smoothly, I might go on to try Linux.
I don't have any experience with this, so I'm asking first. If any of the veterans here have experience, I can avoid some detours.

But seeing the brother in the post above ask that, I guess some systems should work, right?

I'm running DOS on a USB flash drive right now. It seems the drivers aren't right, and a lot of things won't start up.
My laptop uses a USB mouse, and I tried several drivers but still couldn't get the mouse working.
Looks like I need to go learn the basic principles of drivers.
But for now, basic operations are fine, and games can be played, just without sound.

Under DOS, a USB mouse doesn't need a special driver. You just need to enable USB legacy support in the BIOS and load a normal mouse driver.

Turns out the mouse really doesn't need any special driver.
But I still can't get the sound working.

I checked some materials online, and it seems everybody finds sound pretty troublesome.
Some boot disks I found online actually didn't support sound at all.