Hi Eric,


The Standard Install Media (CD, USB, LiveCD, etc) require a 386 or better. 
There are several reasons I have mentioned before why those require a 386. But 
for those who may have missed or forgotten why those require a 386, these are 
the primary reasons. USB did not exist on sub-386 hardware. The CD drivers 
available to FreeDOS require a 386. Finally, the primary installer currently 
uses grep (requires 386+) to parse some of the package lists. (eventually, I’ll 
add some stuff to V8Power Tools to remove the grep dependency.) So, the primary 
installer always installs the packages that may requiring a 386. 

Everything else in this message only applies to the Floppy Edition and it’s 

> On Jul 23, 2023, at 4:47 PM, Eric Auer via Freedos-user 
> <freedos-user@lists.sourceforge.net> wrote:
> Hi!
>> The CPU detection utility used by the installer has compatibility issues 
>> with some processors.
>> For example, there are some 486 systems that are detected as a 186. This has 
>> been a known issue
>> for a while. Unfortunately, I just have not had the time to resolve that.
>> As a stop gap, if the installer is told the system is less than a 386, it 
>> assumes it is incorrect and
>> installs the 386 package set. So, there should be no need to override the 
>> detected CPU on 386+ systems.
> That will just break the complete install on pre-386 systems. If you
> insist on not trusting your tools, at least ASK the user whether they
> want to override the detection.

During the CPU detection, it works its way up through the processors 8086, 186, 
286, etc. If a test fails, then the maximum level of CPU supported is known. 
However, some post-386 machines fail the 286 tests which stops detection and 
returns a maximum support of 80186. 

Since the CPU detection used by the installer cannot reliably detect some 486 
processors at this time, when the installer is told the system has a sub-386 
processor by the detection program, it assumes that is incorrect and to install 
the packages that require a 386 anyway.

Tools that require a 386 or better of zero use on a pre-386 system and are just 
wasting drive space. Space that is even more precious on older systems. 

For example, the XT we had years ago shipped with a 20Mb hard disk. A FreeDOS 
install that includes the useless 386 programs would fill the entire drive. It 
also wastes the users time installing things they cannot use.

However, until I get around to fixing CPU detection, it is better just install 
everything unless.

The user can override this and force installation of only packages that support 
lesser hardware (like 286, 186, 8086). 

> Or better: If the tool detects a pre-386, make sure that you install
> an 8086 compatible kernel. You can still let the config/autoexec keep
> a boot menu item a la "if you are sure that your CPU can actually do
> it, select this item to try to load EMM386 and HIMEM at your own risk."

The Floppy Edition boots the 8086 compatible kernel. By default it will install 
that kernel. 

It ONLY installs the 386 version of the kernel when the system is known to have 
a 386 or better CPU. 

Overriding the package set has no effect and does not apply to which kernel is 
made active on the installed system. 

A user cannot force activation of the 386 kernel when the CPU detection sees a 
lesser CPU. 

This means that on post-386 hardware that is detected as sub-286, the 8086 
kernel is activated. If the user wants to run the 386 kernel, they would need 
to activate it manually. Since it is included with the 386 package set, that is 
very easy to do. 

>> For systems with less than a 386, you will want to override it to ensure the 
>> 8086 compatible kernel
>> is installed.
> This should be the other way round. If you know what you are doing,
> you MAY override the detection result that you have no 386. If you
> do NOT know for sure, then the installer should NOT give you an
> install which would require 386.

Yes and that is what will happen when I someday find the time and motivation to 
resolve the compatibility issue in CPU detection. 

> Of course if the INSTALLER is sure that the CPU is 386 or newer,
> the whole problem does not occur. So my proposal only annoys a
> small number of people with exotic 386+ CPU, but rescues all the
> users with actual 286 or older CPU or emulators from getting an
> un-usable install due to overly optimistic automated overrides.

This is a non-problem. The installer is very pessimistic. At present, everybody 
gets all files and only known 386+ get the 386 kernel activated.

There are multiple 3rd party Youtube videos with users installing the FreeDOS 
floppy edition on sub-386 hardware. Like on real 8086s and emulators like PCem.

Listening to the users of such hardware, they really only have one complaint 
about the Floppy Edition. It is very slow on pre-386 hardware. 

Those users realize the by 8086 software standards, FreeDOS is enormous and 
most of the install time is spent on decompression. 

They could benefit a lot by excluding the 386-only software during 

They could benefit from other improvements to the Floppy Edition as well. For 
example, SLICER (which installer the files) could have everything for the 8086 
stored uncompressed. Or better still, implement a very “high-speed and 
light-weight” compression for those files. It would decrease the compression 
level and probably require a diskette or three more. But, that could really 
speed up installation on such hardware. 

> Regards, Eric


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