Author Archives: Michal Necasek

Seagate Cheetah Date of Manufacture

Posted on May 12, 2020 by Michal Necasek

Lately I found myself in the possession of several Seagate Cheetah 15K.7 SAS drives. These represent the pinnacle of hard disk engineering; with 15,000 RPM, the drives deliver up to around 200 MB/s sustained throughput (both read and write!) and … Continue reading →

Posted in Seagate, Storage, Undocumented | Leave a comment

ThinkPad Audio PnP Hell

Posted on May 4, 2020 by Michal Necasek

The other day I pulled an old ThinkPad 770X (300 MHz Pentium II, good old 440BX chipset, released in late 1998) out of the closet to see if it still works. It does, but I had the terrible idea to … Continue reading →

Posted in Crystal Semi, IBM, Sound, ThinkPad | 14 Comments

Memory Trouble in Stormville

Posted on April 18, 2020 by Michal Necasek

The OS/2 Museum recently acquired a genuine Intel DX79SR (Stormville) board. Together with its close siblings DX79SI (Siler) and DX79TO (Thorsby), these were the last “great” Intel motherboards, supporting the big LGA 2011 socket for the Sandy Bridge E platform—but … Continue reading →

Posted in Bugs, Intel, PC hardware, PC history | 14 Comments

386 Cache Coherency

Posted on April 8, 2020 by Michal Necasek

I’ve been slowly chewing my way through U.S. Patent 5,724,549, titled Cache Coherency without Bus Arbitration Signals, initially filed by Cyrix Corporation in 1992 and published in 1998 (when it was utterly irrelevant, but such is the life of patents). … Continue reading →

Posted in 386, Cyrix, PC architecture, PC history | 17 Comments

Linux 2.4 APIC Hang

Posted on March 16, 2020 by Michal Necasek

The other day I set out to install SuSE Linux 7.3 (Linux 2.4.10 kernel) in a virtual machine, primarily with the goal of evaluating if the included MARS_NWE NetWare emulator is any good. But I couldn’t get anywhere–the boot floppy … Continue reading →

Posted in Bugs, Linux, PC hardware | 16 Comments

OS/2 1.3 on a “Large” Disk

Posted on March 6, 2020 by Michal Necasek

In response to a reader question, I started wondering how difficult it actually is to install OS/2 1.3 on a “big” hard disk, where “big” is defined as more than about 500 MB. In an attempt to reduce the number … Continue reading →

Posted in BusLogic, OS/2, PC history, Storage | 16 Comments

EMM386 and VDS: Not Quite Working

Posted on February 26, 2020 by Michal Necasek

The other day I set out to solve a seemingly simple problem: With a DOS extended application, lock down memory buffers using DPMI and use them for bus-mastering (BusLogic SCSI HBA, though the exact device model isn’t really relevant to … Continue reading →

Posted in Bugs, Development, DOS Extenders | 2 Comments

A Brief Visit to Disk Geometry Hell

Posted on February 20, 2020 by Michal Necasek

Several weeks ago I thought I’d install NetWare 3.12 in a virtual machine using the BusLogic SCSI controller emulation. While configuring a 1.5 GB virtual drive, I thought I should be safe and not run into any trouble with a … Continue reading →

Posted in BusLogic, IBM, NetWare, PC architecture, Storage | 32 Comments

Emulating EtherLink

Posted on January 31, 2020 by Michal Necasek

Spurred by the discovery of a pre-release OS/2 NetWare Requester from early 1988 with a very thin selection of drivers, several months ago I decided to write emulation of the classic 3Com 10Mbps Ethernet 3C501 card, also known as EtherLink. … Continue reading →

Posted in 3Com, Networking, PC hardware, PC history, Virtualization | 33 Comments

1987 Networking: ELS NetWare 286 Level I 2.0a

Posted on January 24, 2020 by Michal Necasek

A rare find recently turned up: NetWare from 1987, specifically the low-end ELS variant of NetWare 286 version 2.0a (ELS may be claimed to mean Entry Level System or maybe Entry Level Server, but at least originally it stood for … Continue reading →

Posted in 286, 3Com, Kryoflux, NetWare, Networking | 29 Comments