Maybe that is useful for somebody, so I make a thread here.
We all know that some games / programs need a big amount of free DOS memory (640k)
When using orginal MS tools (MS DOS 6.22 or DOS 7.1 from Windows 98SE), you need to use EMM386.EXE to enable the upper memory. Only then devicehigh= and loadhigh will work.
Using EMM386 will switch the CPU to protected mode. That makes some games slower for example DOOM. So we do not want that 😁.

So EMM386 is ONLY used when we really need expanded memory, so only in rare cases.

For early pentium mainboards one can use UMBPCI.SYS, described here: https://www.mdgx.com/mem7.htm

But that does not work on 486 mainboards as far as I know. Boards with a SIS471 do not have PCI at all.
So for SIS 471 boards there is a solution, too: It is UMBSIS.SYS!
https://www.uwe-sieber.de/util_e.html

I use it for my Asus SV2GX4 with Windows 98SE:

config.sys:

1[menu]
2menuitem=windows, Microsoft Windows 98 Second Edition
3menuitem=DOS1, MS-DOS 7.10 - XMS
4menuitem=DOS2, MS-DOS 7.10 - EMS
5menudefault=windows, 10
6
7[windows]
8device=C:\WINDOWS\COMMAND\display.sys con=(ega,,1)
9Country=043,850,C:\WINDOWS\COMMAND\country.sys
10
11[DOS1]
12SWITCHES=/E
13DEVICE=C:\WINDOWS\HIMEM.SYS
14DEVICE=C:\DRIVERS\UMBSIS4.SYS
15DOS=HIGH,UMB
16DEVICEHIGH=C:\DRIVERS\VIDECDD.SYS /D:MSCD001
17FILES=30
18BUFFERS=30,0
19LASTDRIVE=F
20
21[DOS2]
22SWITCHES=/E
23DEVICE=C:\WINDOWS\HIMEM.SYS
24DEVICE=C:\WINDOWS\EMM386.EXE RAM
25DOS=HIGH,UMB
26DEVICEHIGH=C:\DRIVERS\VIDECDD.SYS /D:MSCD001
27FILES=30
28BUFFERS=30,0
29LASTDRIVE=F

autoexec.bat:

1goto %config%
2
3:windows
4mode con codepage prepare=((850) C:\WINDOWS\COMMAND\ega.cpi)
5mode con codepage select=850
6keyb gr,,C:\WINDOWS\COMMAND\keyboard.sys
7C:\WINDOWS\WIN.COM
8goto end
9
10:DOS1
11lh c:\drivers\keyb2.com
12LH C:\WINDOWS\COMMAND\DOSKEY.COM
13LH C:\drivers\ctmouse.exe
14LH C:\WINDOWS\COMMAND\MSCDEX.EXE /D:MSCD001
15goto end
16
17:DOS2
18lh c:\drivers\keyb2.com
19LH C:\WINDOWS\COMMAND\DOSKEY.COM
20LH C:\drivers\ctmouse.exe
21LH C:\WINDOWS\COMMAND\MSCDEX.EXE /D:MSCD001
22goto end
23
24:end

In msdos.sys there is
BootGUI=0
and
Logo=0

Some remarks:
The Windows 98 startup is unmodified, it is exactly the same as after the installation of a German Windows 98SE.

The interesting part is the section DOS1 => XMS. There is no EMM386 but still loading high works. More or less everything can be loaded high, so I also use a german keyboard driver, doskey, mouse driver and a CD ROM driver.

UMBSIS4.SYS is used in my case, because I use a XTIDE BIOS located on C800
see table below, that is documented on the Uwe Sieber page.

UMBSIS1.SYS 32K: C800-CFFF
UMBSIS2.SYS 160K: C800-EFFF only for memory size 16MB and more.
UMBSIS3.SYS 96K: C800-DFFF
UMBSIS4.SYS: 128K: D000-EFFF
UMBSIS5.SYS: 64K: D000-DFFF
UMBSIS6.SYS: 64K: E000-EFFF