Most people who grew up with MSDOS on 16bit 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:

Lotech 1MB RAM card: https://texelec.com/product/lotech1...

PCjr jrIDE sidecar: https://texelec.com/product/jridefo...

All the software mentioned in this video is available via anonymous FTP: http://ftp.oldskool.org/pub/youtube/d...

==========

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

https://bit.ly/DOScember2020

Also check out these other #doscember participating Channels:

Adrian's Digital Basement:    / adriansdigitalbasement  
ctrlaltrees:    / ctrlaltrees  
DaveJustDave:    / mrdavejustdave  
Jan Beta:    / janbeta  
Josh Malone:    / joshmalone_48kram  
LGR:    / lazygamereviews  
MindFlareRetro:    / mindflareretro  
Mr Lurch's Things:    / mrlurchsthings  
Noel's Retro Lab:    / noelsretrolab  
RetroSpector78:    / retrospector78  
RMC:    / rmcretro  
RoseTintedSpectrum:    / rosetintedspectrum  
Tech Tangents:    / akbkuku  
The 8Bit Guy:    / adric22  
TheRetroChannel:    / theretrochannel  

==========

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

Want to support me, and help me make more videos like this? Consider becoming a patron:   / theoldskoolpc  

Some incidental music by coda, used with permission: https://coda.s3m.us/

Contact info:
Twitter: @MobyGamer
Email: http://www.oldskool.org/personal