Breaking the DOS 640k barrier on 8086 and 80286 systems

Most people who grew up with MS-DOS on 16-bit 8086 and 80286 CPUs learned about the 640K limit and accepted it -- but you may be surprised to know that 640K isn't the actual limit. In this video, I explain why the 640K limit is a myth, and how you can break past it using a variety of methods that don't require EMM386 or an 80386 CPU.

Chapters:

00:00 Intro
00:51 Benefits
01:43 The IBM PC Memory Map
02:48 The orthodox procedure
04:09 What are Upper Memory Blocks?
04:53 Orthodox procedure continued
06:46 An Unorthodox procedure
09:34 Q&A
11:31 DOScember

Hardware and software mentioned in this video:

Lo-tech 1MB RAM card:

PCjr jrIDE sidecar:

All the software mentioned in this video is available via anonymous FTP:

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This video was a part of #DOScember ! Here's the #doscember official playlist:

Also check out these other #doscember participating Channels:

Adrian's Digital Basement:
ctrl-alt-rees:
DaveJustDave:
Jan Beta:
Josh Malone:
LGR:
MindFlareRetro:
Mr Lurch's Things:
Noel's Retro Lab:
RetroSpector78:
RMC:
RoseTintedSpectrum:
Tech Tangents:
The 8-Bit Guy:
TheRetroChannel:

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Thanks to winworldpc for supplying some software, and to Mike Brutman for boot sector patch ideas.

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Some incidental music by coda, used with permission:

Contact info:
Twitter: @MobyGamer
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