Windows 98SE comes with MS-DOS 7.10.
So, yes. You can dual boot between DOS 7.10 and Windows 98SE by simply setting up a start menu configuration within your Autoexec.bat & Config.sys files.
You also need to edit your MSDOS.SYS file (in your root folder) in order to bypass the GUI.
The benefit of this is that this can be set up on the same partition.

However, it sounds to me that you already have MS-DOS 7.10 installed and running Windows 3.1 on it? As soon as you install (or upgrade to) Windows 98SE, you will have to set up the start menu configuration that I described above.
You can probably set up a separate partition or plug in another hard drive, but this requires careful planning and tinkering.
If you are upgrading on the existing partition, then Windows 98SE should migrate your Windows 3.1 settings and applications, but I would still recommend a full backup.

Personally, I would backup everything and do a fresh installation.

Yes its possible dual boot or multi boot with every kind of o.s you just need the right partition manager and boot loader
Edit: here is the link of the video where i'm show how to multi boot with any O.S https://www.youtube.com/watch?v=Qz1gQORp7PU

Since I'm soon going to buy a new IDE hardisk (probably 300 GB or 500 GB), I'll just do the partitions the first time with Partition Manager and install the systems without touching anything on the one I currently have (except moving all the data to the DOS I'm going to install on the new one)... only one thing: which order should I install the systems ?
I'll probably go for DOS, 98 and MAYBE also XP (but probably I'll just keep DOS and 98 with the extra space as "secondary drives for extra space"), but... saying I install DOS, 98 and XP, which order should I go ? Like... DOS, then 98 and then XP ? To have a boot OS selection menu with all of three at the startup, you know...

Hi, Elia1995, if you just want to multi-boot two operatings systems, there's a much simpler way to do it.
Just set one hard drive to cable select and connect a switch to the other ones jumper pins.
When you flip the switch, the hdds switch their order and you can safely access both of them.
The schematic is somewhere..

Here's something similar, just using the cable instead!

Make a Dual-Boot IDE Cable

Windows 98SE can boot to DOS simply by pressing F8 during startup and selecting "Command Prompt Only" from the menu. (I think F4 or one of the other function keys might work without even having to go to the menu; I forget the details.) If you're concerned about Windows 98 Setup obliterating a pre-existing Windows 3.1 installation, then just make sure you back up first. 😀

As for dual-booting with XP, I don't think XP and Windows 98 can coexist on the same partition (or at least not without a substantial amount of trickery). If you store them on separate primary partitions, then if you want, you can dispense with a boot manager and just toggle which one will boot by setting the active partition. This is easily done in XP's Disk Management; from DOS, you can use fdisk or a similar tool (like Norton Gdisk).

So if I install them on separate hard drives can I still get automatically something like an OS selection screen with some kind of program ?

The trouble with using "some kind of program" is that it's very easy to accidentally mess something up and make it impossible to boot from your hard drive (at least until you get out a boot floppy and fix the thing you accidentally messed up). See Recommendation for DOS/win9x boot manager? for possibilities. Come to think of it, I guess you can manually edit the XP boot menu configuration so you could boot from an OS on another partition or drive; it's been a long time since I've poked at it.

If you use separate hard drives (not separate partitions, but separate drives) then you can also just switch the boot order in the BIOS when you need to.

Did you get this working? How did you do it in the end?
(just interested that's all)

I have something similar with win95 and Dos and Win3.11

1. After installing Win95 edit msdos.sys and set bootgui=0 to stop booting at Dos Prompt, you can start win95 by typing Win.

2. patching io.sys so that win 3.11 accepts it.

3. backing up config.sys and autoexec.bat

4. Installing win3.11 (to another folder or drive than win95) and changing path in config.sys and autoexec.bat

5. make a boot menu in config.sys with win95, win3.11 and Dos.

6. then put the right lines from config.sys and backed up config.sys to the menublocks of win95 and win3.11.

after starting you can choose between win95, win3.11 and dos (maybe more dos versions, Dos-xms, Dos-emm, etc)

But all depends on that Dos that comes with your windows version..
So it is not possible to boot 7.1 for win98 and 6.22 for win3.11.
If you use win98 then all windows95, win3.11, dos-programms, and dos-games run under Dos 7.1

I made a quad boot with Dos 6.22, Windows 95, Windows 98SE and OS2 Warp4 on one harddisk. I used PQ Partition Magic and PQ Boot Magic as bootmanager, but there are also other programs to accomplish this.

First I made 4 Primary partitions an one extended, yes that is possible, as long as the partitions are not active. Than I just activated the first partition as C:, installed the first OS, than I Activated the second partition as C: and deactivated the first, than installed the next OS... and so on. First I did only an OS installation without any drivers update and whatever, because when something goes wrong and I have to start again , it's less time. Than I Installed Boot Magic (you can do this on 95 or 98, there is also a Dos version but I prefer the windows one), and configured it that way that whatever OS I chose the other Partitions will be deactivated so every OS sees only the C: drive and the extended for data as D:

chinny22 wrote:

Did you get this working? How did you do it in the end?
(just interested that's all)

I haven't worked on that yet, although I'm planning to install 95 instead of 98SE and I will in a separate hard disk, just as I did with the Windows 98 PC, in which I added a second hardisk and installed XP in it and got it dual boot with XP and 98SE.

Why all this work? Changing jumpers and stuff!
Just use extended fdisk. And you wont even have to tweak Win98 in order to set up some DOS setup. And other strange setup procedures.

Roman78 wrote:

I made a quad boot with Dos 6.22, Windows 95, Windows 98SE and OS2 Warp4 on one harddisk. I used PQ Partition Magic and PQ Boot Magic as bootmanager, but there are also other programs to accomplish this.

First I made 4 Primary partitions an one extended, yes that is possible, as long as the partitions are not active. Than I just activated the first partition as C:, installed the first OS, than I Activated the second partition as C: and deactivated the first, than installed the next OS... and so on. First I did only an OS installation without any drivers update and whatever, because when something goes wrong and I have to start again , it's less time. Than I Installed Boot Magic (you can do this on 95 or 98, there is also a Dos version but I prefer the windows one), and configured it that way that whatever OS I chose the other Partitions will be deactivated so every OS sees only the C: drive and the extended for data as D:

Yeah...
All a bootmanager does, is to set the active flag on any prtition (most likely only primaery ones, I dont know for shure), and that active flag is still set untill it is changed by the user. Even when after a reboot.

This is at an advantage, whenever you are installing a new OS. Just install the manager and add a wanted number of partition. Then you can set the bootable flag on any empty unformatted partition, and reboot with the OS install Media. The default partition is allways the active.

This way you make it all work to you'r advantage when installing stuff like Win98 and MS-Dos-6.22

For the OP....
I actually think that I have seen MS-Dos-7 as a standalone Windows98 free Installer, a couple of years ago.

The thing is, I don't wanna mess up my DOS 7 installation because I also have Win 3x installed in it.
If by accident I install 98SE wrongly, I cannot boot Win 3x anymore, because of WIN command conflict, Windows folder conflict and other fancy stuff.

You cannot "boot" Win3.x, because Win3.x is not an OS. It is just an application that runs on top of DOS.

Win9x in some ways is the same, but it does replace more DOS subsystems with its own, probably enough to justify calling it an OS. Still, the main boot stuff is handled by the DOS subsystem.

Formally, MS-DOS 7.10 is not a thing, because I think that officially at least it was never distributed separately from Win98 (except maybe for emergency boot environments). So in some way you are just asking to dual boot Win98 with Win98... 😀 But I do see what you are trying to do.

I think that you can find a way to have a single boot partition, where Win98 will be the main Windows, and Win 3.x will be run from a separate Windows directory somewhere, and avoid conflicts, but it would probably be safer to have them on separate partitions, with completely separate installation bases, and an external boot manager.

brostenen wrote:

Roman78 wrote:

First I made 4 Primary partitions an one extended, yes that is possible, as long as the partitions are not active.

Yeah...
All a bootmanager does, is to set the active flag on any prtition (most likely only primaery ones, I dont know for shure), and that active flag is still set untill it is changed by the user. Even when after a reboot.

If there are four primary partitions and one extended, there will definitely have to be some fancy trickery involved.

Elia1995 wrote:

The thing is, I don't wanna mess up my DOS 7 installation because I also have Win 3x installed in it.
If by accident I install 98SE wrongly, I cannot boot Win 3x anymore, because of WIN command conflict, Windows folder conflict and other fancy stuff.

What is this "WIN command conflict"? If you type "win.com" at the MS-DOS prompt, it will either look in the current directory for "win.com", or it will start searching the directories in the PATH environment variable. There's nothing magical there.

As far as "Windows folder conflict" is concerned, you don't have to install either of Win3.x or 98SE to C:\WINDOWS. If you already have Win3.x installed to C:\WINDOWS, just install 98SE to C:\WIN98 or something. (There are probably some very-badly written programs that assume Windows must be installed to C:\WINDOWS, but badly-written programs are inevitable. 😜 )

It's even possible to run Win3.x without exiting Win9x, but some versions require a patch to make it work.

As I said above: if you're worried about breaking something, just back up first. You might want to use a drive imaging program. There are lots of those, like Paragon or Macrium Reflect.

Elia1995 wrote:

The thing is, I don't wanna mess up my DOS 7 installation because I also have Win 3x installed in it.
If by accident I install 98SE wrongly, I cannot boot Win 3x anymore, because of WIN command conflict, Windows folder conflict and other fancy stuff.

Make a systembackup whit Norton Ghost or some other backuptool before experimenting.