Linked Questions

50 votes
11 answers

What is the oldest computer capable of running a modern version of GNU/Linux?

A bit of a trivia question: What is the oldest hardware capable of running a modern Linux-based operating system, including user-space? (Not necessarily GNU userspace, but running a standard GNU/Linux ...
Jonas Czech's user avatar
55 votes
8 answers

Why didn't the 8086 use linear addressing?

The 8086 used a segmented memory architecture where the linear address was computed from a 16-bit segment number and a 16-bit offset. This greatly complicated things from a programming perspective. ...
Alex Hajnal's user avatar
  • 9,350
17 votes
8 answers

Why was the DOS kernel discarded?

I've read that the last DOS kernel based Windows was ME. Later versions use the NT kernel. Why did Microsoft rewrite the whole kernel? Why was the DOS kernel discarded?
zomega's user avatar
  • 5,372
33 votes
3 answers

How was the 80186 incompatible with the IBM PC?

Wikipedia's Intel 80186 entrymentions The 80186 would have been a natural successor to the 8086 in personal computers. However, because its integrated hardware was incompatible with the hardware used ...
rwallace's user avatar
  • 62.6k
14 votes
3 answers

Why does PC video memory base address change depending on video mode?

It is rather well-known that, with VGA-compatible PC video adapters, in black-and-white text modes video memory is available at linear address 0xB0000, in colour text mode at address 0xB8000, while in ...
user3840170's user avatar
  • 23.1k
16 votes
4 answers

Did the Intel 8086/8088 not guarantee the value of SS:SP immediately after RESET?

I'm poking at the Intel 8086/8088 (iAPX 86/88) User's Manual, which states on page 2-29 (PDF page 48), table 2-4, CPU State Following RESET, that the state of the CPU after the RESET pin rising ...
user's user avatar
  • 5,326
15 votes
4 answers

Can DOS make use of more than 640 KB of conventional memory on 80186?

Can I have more than 640 KB conventional RAM under some DOS? I'm looking at an 80186 PC that has RAM at address A0000. Video RAM starts at B0000 as expected for a Hercules; A0000 is just more main ...
Joshua's user avatar
  • 1,839
10 votes
2 answers

How to use all memory on an IBM PC with 8086

I'm developing software for the IBM PC with an 8086 processor. I want my program to use all available memory. I know that I can use DOS int 21h function AH=48h to allocate all available conventional ...
pts's user avatar
  • 2,013
7 votes
3 answers

Is there really 1MiB of physical memory in the motherboard of a PC AT/XT?

This is a question that has been puzzling me for a while. What happens with devices like graphic cards that have their own memory chips? Do these cards read/write from their own internal memory to/...
Trap's user avatar
  • 329
4 votes
1 answer

Origin of "640K RAM is enough" quote

Yesterday I was digging through a rather long directory path to watch an episode of Fist of the North Star (on Windows 8.1) when I was hit with an error message: The path name is too long I looked ...
Yamcha_Kippur's user avatar