Author Archives: Michal Necasek

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

Fake vs. Real

Posted on March 2, 2021 by Michal Necasek

After discussing an Adaptec SCSI HBA that was clearly made from recycled parts and likely fake, I wanted to see what a real one looks like. It looks like this: For reference and for comparison, here’s the sketchy one: The … Continue reading →

Posted in Adaptec, Fakes, PC hardware | 6 Comments

Diskette Puzzle

Posted on February 25, 2021 by Michal Necasek

Last week the OS/2 Museum received a classic red NetWare box with all sorts of junk inside: PCI and ISA network cards (most Ethernet, one ArcNET), BNC cabling, one or two manuals, and over a 100 floppies, mostly NetWare but … Continue reading →

Posted in Archiving, Floppies, NetWare | 20 Comments

Complications, Complications

Posted on February 19, 2021 by Michal Necasek

The other day someone asked how hard it would be to modify the Open Watcom linker, wlink, to properly support exports from IOPL segments in OS/2 LX modules. Not terribly hard it turned out, all it needed was to emit … Continue reading →

Posted in Development, OS/2, Watcom | 2 Comments

SCSI HBA Recycling?

Posted on February 10, 2021 by Michal Necasek

Several weeks ago I bought this Adaptec 39160 64-bit PCI SCSI HBA in order to experiment with different HBAs: The motivation was that although I’ve been a happy user of LSI HBAs (SCSI and SAS, PCI and PCIe) based on … Continue reading →

Posted in Adaptec, Fakes, PC hardware, SCSI | 10 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 | 12 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

DDR2 4GB DIMMs

Posted on January 29, 2021 by Michal Necasek

Last week the OS/2 Museum got its first ever set of real (i.e. not fake) 4 GB DDR2 desktop (unbuffered) DIMMs, a pair of Samsung 4GB PC2-6400U modules. Such modules are quite rare and correspondingly tend to be unavailable at … Continue reading →

Posted in DDR RAM, Fakes, PC hardware | 23 Comments

Booting Windows XP, Or Not

Posted on January 22, 2021 by Michal Necasek

For a number of years now I’ve been using a SATA SSD with a “portable” Windows XP installation on it. Portable in the sense that it was capable of booting on a number of my machines, either in IDE mode … Continue reading →

Posted in Debugging, PC hardware, Windows XP | 16 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