Citation needed because honestly, I&#x27;ve never heard of this and I think you&#x27;re confusing it with something else. I&#x27;ve been using computers since the introduction of the original IBM PC and have had to spend a lot of time dealing with memory issues over the years.<p>&quot;Extended memory&quot; drivers were a common thing back then but that was to circumvent the 640KB&#x2F;1MB limit of DOS and they had nothing to do with video card memory. In that era few people even knew how much memory was on their video card because it was rarely a concern, most of the time it was just barely enough to hold a single frame buffer, typical of most VGA and &quot;Super-VGA&quot; cards.<p>Extended memory is that which is beyond the boundaries of the original IBM PC design: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Extended_memory" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Extended_memory</a><p>It&#x27;s not video card memory in any way. If I recall correctly the video card memory was often mapped into the 640KB-1024KB memory zone, but using that for system memory was futile since you&#x27;d be unable to see anything on screen.