I second this. PCI graphics cards usually have 1 MB or more of video memory. And a RAMDAC capable of direct-colour mode. They can display 1024x768 pixels beyond 256c.
ISA VGA cards, by contrast, have 256 KB or 512KB/1MB and sometimes come with a RAMDAC
that is using palette mode only (256c simultaneously, out of a palette of.. 4096c?).
They can display 800x600 and 1024x768 pels easily, though ! But not necessarily using progressive scan, a high refresh rate and with more than 256c.
PS: The IBM 8514/A from 1987 could do 1024x768 pels in 256c at 46 Hz refresh (interlaced)! Flickery, but hi-res, at least. Aiming at the lower CAD/DTP sector, so to say.
Edit: 1024x768 was the resolution we used at school to create the school's website.
But we didn't expect 16-Bit colour depth, rather used web safe colours.
The pictures on the site were JPEGs already, though, so maybe using 16-Bit colours.
GIFs of the early internet days had a 256c limit (Windows could display 236c merely, the rest was reserved).
Edit: Or to put things into perspective:
1024x768 in 16-Bit was a normal Windows 98SE resolution in the 2000s.
Problem was, that many Windows 98SE owners kept using their 90s hardware still (98 still ran on 486 PCs).
In the late 90s, 256 colour resolutions were still being common - even though not end of the line, either.
Users with an AGP graphics card had no problem using both high resolutions/colour-depths, they were rather handicapped by their CRT monitors.
On the other "extreme", 1024x768 or 1280x1024 or -gasp- 1600x1200 in 16-Bit/24-Bit were used way down in 1992 - on Windows 3.1x.
By DTP people and professional photographers (Kodak Photo CD..) and other artists.
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