Category Archives: PC history

8237A DMA Page Fun

Posted on March 28, 2021 by Michal Necasek

The other day I was trying to fill a couple of gaps in my understanding of the Intel 8237A DMA controller documentation. I wrote a small testcase that performed a dummy transfer and modified the base address and count registers … Continue reading →

Posted in Intel, PC architecture, PC history | 5 Comments

Nehalem and 4 Gbit DDR3

Posted on February 5, 2021 by Michal Necasek

While discussing Intel desktops with DDR2 memory using 2 Gbit technology (4 GB UDIMMs), the question of Intel’s next generation and 4 Gbit DDR3 (8 GB UDIMMs) came up. It’s more or less the next iteration of exactly the same … Continue reading →

Posted in Intel, PC hardware, PC history | 10 Comments

The Phantom Intel GM47 Chipset

Posted on February 2, 2021 by Michal Necasek

I spent a bit of time recently putting together technical documentation for Intel’s 4-series chipsets, partly motivated by research into Intel’s support of 4 GB DDR2 memory modules, partly driven by idle curiosity about one of Intel’s many hyped up … Continue reading →

Posted in Intel, PC history, PC press | 7 Comments

Seek and Ye Shall Find…

Posted on January 20, 2021 by Michal Necasek

…in the strangest places! Lately I’ve been digging up marketing materials related to Intel’s desktop boards (I’ve long been toying with the idea of writing up a brief history of the circa 10 years of Intel Extreme Series boards). There … Continue reading →

Posted in Archiving, Intel, PC hardware, PC history | 2 Comments

It’s In Style Now

Posted on January 10, 2021 by Michal Necasek

Retrocomputing has now made it to the Style section of the New York Times. There is nothing particularly new about the article, except where it appeared. I guess people have noticed that retrocomputing is a thing, and that old gear … Continue reading →

Posted in PC history, PC press | 10 Comments

The Answer To 0x49: Fujitsu FMR

Posted on December 11, 2020 by Michal Necasek

This is a guest post by A. N. Other. The following was originally intended as a comment to “Not MSX Either“, the 4th installment in the hunt for the mysterious 0x69 FAT VBR-start byte which was allowed in DOS. Due … Continue reading →

Posted in DOS, NT, PC hardware, PC history, Undocumented | 7 Comments

Decoding Seagate Date Codes

Posted on November 27, 2020 by Michal Necasek

More or less everyone knows that throughout the 1990s and 2000s, Seagate did not label their drives with a date of manufacture like everyone sane would do, but instead used a custom and somewhat mysterious/confusing “date code”. For reasons that … Continue reading →

Posted in PC history, Seagate, Storage | Leave a comment

Those Lot Numbers are Old

Posted on October 24, 2020 by Michal Necasek

The other day I was trying to decode the “lot numbers” printed on certain Seagate drives. In the meantime, I realized that those lot numbers have been in use for quite some time. They were in use around 2000, like … Continue reading →

Posted in PC history, Seagate | 11 Comments

Not MSX, Either

Posted on October 7, 2020 by Michal Necasek

Further examining the mystery of boot sectors supposedly starting with byte value 69h, I considered the possibility that the check could have been added for MSX machines. The MSX platform ticks a lot of boxes: It wasn’t 8086 (but rather … Continue reading →

Posted in IBM, Microsoft, PC history | 15 Comments

Really Atari ST?

Posted on September 21, 2020 by Michal Necasek

This blog has previously examined a very very strange code fragment in the BIOS module of DOS. To recap, when deciding whether a boot sector might have a valid BPB, DOS checks whether the first byte is a relative jump … Continue reading →

Posted in DOS, Microsoft, PC history | 18 Comments