Category Archives: Graphics

Windows 3.x VDDVGA

While working on my Windows 3.x display driver, I ran into a vexing problem. In Windows 3.1 running in Enhanced 386 mode, I could start a DOS session and switch it to a window. But an attempt to set a … Continue reading

Posted in 386, Development, Documentation, Graphics, PC history, Windows | 59 Comments

Reconstructing the EGA BIOS

A few weeks ago I had a sudden need to understand certain finer points of the operation of EGA/VGA BIOS. I found common reference materials to be inadequate—they tend to do a good job of documenting the data structures the … Continue reading

Posted in BIOS, Development, Documentation, Graphics, IBM, PC history | 32 Comments

Broken Spigot

While searching for an unrelated piece of hardware, I came across an old video capture board. Alarm bells started going off when I heard something rattling in the anti-static wrap. Sure enough, one of the large capacitors fell off… because … Continue reading

Posted in Graphics, PC hardware, PC history | 3 Comments

sips To the Rescue

A few days ago I scanned a document and unwisely used MS Paint on Windows 7 to touch up a small selection of the scanned pages. Once the dozen or so files were re-touched, I combined them into a PDF … Continue reading

Posted in Graphics, OS X | Leave a comment

A Tale of Two Displays

By sheer coincidence, two new computers arrived in my family at almost the same time, and they couldn’t be more different. At first sight, the most striking difference is the quality of their displays, and it says a lot about … Continue reading

Posted in Apple, Graphics, PC hardware | 10 Comments

NT Video Miniport for VirtualBox, With Source Code

Note: See also an updated version. Upon reader request, the OS/2 Museum is publishing the source code to the NT video miniport driver for VirtualBox. To recap, this is a NT video miniport which allows 32-bit NT versions to use high-resolution graphics … Continue reading

Posted in Graphics, NT, Source code, VirtualBox | 48 Comments

S3 Fraternal Twins

Sometimes identifying old hardware is a bit tricky. Consider these two graphics cards: The PCB is the same, the BIOS chips look the same, the DAC is slightly different but an 80 MHz part in both cases, memory is the … Continue reading

Posted in Graphics, PC hardware, S3 | 5 Comments

The ISA OSC Mystery

About twenty years ago I ended up with a spare ISA graphics card from an upgraded computer. It was a SVGA card based on the Cirrus Logic CL-GD5422 chip, equipped with 1 MB video memory. This was a very cheap … Continue reading

Posted in Cirrus Logic, Graphics, PC hardware | 15 Comments

Early PCI Board

Since some of this blog’s readers are very good at recognizing obscure hardware, I thought I’d post photos of one more somewhat exotic graphics card: This board was one of the early PCI graphics adapters. It’s old enough that it … Continue reading

Posted in Graphics, PC hardware | 27 Comments

Two More TIGAs

Since some readers appear to enjoy identifying prehistoric graphics cards, I thought I’d post photos of two more TIGA boards from my junk pile. I know what these are, but do you? One of them ought to be fairly easy … Continue reading

Posted in Graphics, PC hardware | 14 Comments