Booting DOS 7.1 on system with 4 gb ram (not enough for Smartdrive?)

[rloew]

A "normal" MSDOS.SYS contains a pointer to a Windows folder containing HIMEM.SYS.

A DOS Floppy has a dummy MSDOS.SYS to prevent DOS from searching for Windows.

With IO.SYS 7 HIMEM.SYS is mandatory.

With IO.SYS 7 CONFIG.SYS with a HIMEM entry is required when using a dummy MSDOS.SYS File.

@Jaclaz

1. HIMEM.SYS is not needed with IO.SYS 8.

2. Nothing

3. Nothing.

@Tripredacus

The memory problem only appears if you use EMM386 or something else that actually tries to use more than 2.5GB and uses the HIMEM 2.0 protocols.

DOS doesn't care.

SMARTDRV only uses a few Megabytes.

[submix8c]

Can someone clarify what a "valid" vs "invalid (missing?)" MSDOS.SYS constitutes?

https://support.microsoft.com/en-us/kb/118579

http://www2.yk.psu.edu/~lxn/IST_226/ist_226_win9x_msdossys.htm

BTW, the IO.SYS in the "real" WinME is significantly different from the XP/2K3 one (Used the Decompiler). I suppose that this file is what constitutes "DOS7" being referenced? Aside from the "missing" files in the XP/2K3 WinME (EBD), that's the only one that's apparently different.

 

And at the risk of being laughed at because... Wiki -

https://en.wikipedia.org/wiki/Windows_ME#Hardware_support_improvements

http://web.archive.org/web/20070308152728/http://www.microsoft.com/whdc/archive/fast-boot.mspx

[dencorso]

Nowadays, with current BIOSes etc. using part of the UMA for USB native support and another part of the UMA for SATA native support, there's hardly any UMB memory to be recovered. So, it's difficult to justify using EMM386.EXE. If not using it, the handles problem does not happen, and a (real or virtual) floppy or pendrive booting solely with IO.SYS, COMMAND.COM, HIMEM.SYS, SMARTDRV.EXE and a dummy MSDOS.SYS should work great, but adding a CONFIG.SYS to load both HIMEM and SMARTDRV (as a INSTALL= line) is quite handy, and can accomodate CD/DVD drivers, too, if needed. I'll justify this later, but the best choice for those files is using those that come with Win 98SE, not those from ME, and in all cases, replacing IO.SYS by the one from KB311561 (use the EBD version for ME).

The attached image is a screen capture in plain DOS 7.1 (without EMM386), acquired with the good old Screen Thief for DOS v2.04, of the map of the upper memory area of my P8Z68-V LX motherboard, generated by the good old UMASCAN, by Jeff Prosise. As you all can see, there's just 64 kiB available for the creation of a UMB...

[jaclaz]

@dencorso

Very good and interesting, but the questions  (at least mine) were not about the best possible configuration, but rather what are the minimum requisites for the install XP from DOS having SMARTDRV correctly loaded, the actual practical scope of that is just to copy (as fast as possible) the XP install files from (USB) source to internal hard disk and later to run WINNT.EXE.

 

Rloew replied to those nicely:

 

 

The questions are now:

1. Would the same do with Windows ME (or embedded in XP) boot floppy files? (I presume yes, but maybe the SMARTDRV has issues with them )
2. What has to be changed when using as base the same Windows 98 boot floppy files when there are more than 2.5 Gib of RAM? (I would give that the MSDOS.SYS file is untouched, is just adding the HIMEM.SYS be OK?)
3. What has to be changed when using as base the Windows ME (or embedded in XP) boot floppy files when there are more than 2.5 Gib of RAM? (given that one way or the other a form of HIMEM.SYS is "embedded" in IO.SYS?)

 

 

 

@Jaclaz
1. HIMEM.SYS is not needed with IO.SYS 8.
2. Nothing
3. Nothing.
 

 

So, all is needed now is that someone with more than 2.5 Gb verifies by trying to install that way:

a. With just the Windows Me/DOS 8.0 bootdisk (the one that can be extracted from XP) files IO.SYS, MSDOS.SYS and Command.com

b. With the Windows 98 bootdisk files, adding to the three files IO.SYS, MSDOS.SYS and Command.com also the HIMEM.SYS

(of course besides the FreeDOS Fdisk and the XCOPY files).

 

jaclaz

[dencorso]

Well, for what it's worth, I've checked and all versions of diskcopy.dll, from XP up to 7 including the 32-bit one from the WOW64 folder of 7 ultimate SP1 yield the exact same floppy image when extracted with Nuno Brito's DISKEXTRACT. That image is a modified version of the original Win ME ebd floppy, and can only behave exactly like it, in all relevant aspects.