Author Archives: Michal Necasek

Zapping the SVP on a T42p

Posted on April 29, 2016 by Michal Necasek

A T4x ThinkPad with a supervisor password is a ticking time bomb. The password is not needed during boot and is only required to change certain BIOS settings, something which isn’t typically needed. But if CMOS settings are lost, the … Continue reading →

Posted in Hardware Hacks, ThinkPad | 4 Comments

Can a DB-50XG Talk?

Posted on April 27, 2016 by Michal Necasek

I seem to have embarked on another crazy research project. It was spurred by a broken Yamaha DB-50XG wavetable daughterboard. The DB-50XG was a bit dirty but not obviously damaged. It produces no output but gets warm exactly like a … Continue reading →

Posted in Sound, Wave Blaster, Yamaha | 1 Comment

Solaris 7 Boot Panic

Posted on April 23, 2016 by Michal Necasek

On some systems, it has been observed that Solaris 7 panics during boot from installation media and reboots the system. At least Solaris 7 U1 (3/99) and U4 (11/99) are affected. Only “fast” systems (definitely including Sandy Bridge 3+ GHz … Continue reading →

Posted in Bugs, Debugging, Solaris | 6 Comments

IBM OS/2 1.x Programming Documentation Added

Posted on April 15, 2016 by Michal Necasek

IBM’s programming documentation (Programming Tools and Information, aka PTI) for OS/2 versions 1.2 and 1.3 has been added. Big thanks to Bob Eager who scanned the originals and converted them to PDF. The documents have been added to the OS/2 … Continue reading →

Posted in Development, Documentation, IBM, OS/2 | 2 Comments

PCI Voodoo

Posted on April 5, 2016 by Michal Necasek

A while ago I tried to set up Voodoo 2 SLI on an old Pentium system running Windows 98 SE. I used two seemingly identical Creative CT6670 boards (Voodoo 2, 12 MB RAM) which should have worked just fine. But … Continue reading →

Posted in 3Dfx, PCI | 31 Comments

Children of the Bus Wars

Posted on March 23, 2016 by Michal Necasek

In the late 1980s and the early 1990s, the so-called Bus Wars raged. A few years after the PC/AT was released, it became clear that the ISA bus could not keep pace with faster CPUs and peripherals, especially graphics cards … Continue reading →

Posted in ATi, EISA, MCA, PC history, PCI, VLB | 11 Comments

Fixing a Graphics Ultra Pro

Posted on March 13, 2016 by Michal Necasek

Just a few weeks after successfully repairing a trivial problem with a Roland LAPC-I caused by improper storage, I happened to run across another troublesome board, a VL-bus based ATI Graphics Ultra Pro from 1993. It’s a nice enough card … Continue reading →

Posted in ATi, Hardware Hacks | 4 Comments

Seagate ST-225: Just Wow

Posted on March 4, 2016 by Michal Necasek

A few weeks ago a Seagate ST-225 drive more or less accidentally landed at the OS/2 Museum. The drive is nearly 30 years old (manufactured in late 1986) and rather interestingly, this particular unit comes with a label declaring it … Continue reading →

Posted in PC hardware, Storage | 35 Comments

Periscope Manuals

Posted on March 1, 2016 by Michal Necasek

Some time ago I recovered a latter-day Periscope manual from storage. Since some readers might find it useful, I decided to scan the manual and convert it to PDF. It covers the basic Periscope debugger, variants and add-ons (remote Periscope, … Continue reading →

Posted in Debugging, Documentation | 7 Comments

Fixing an LAPC-I

Posted on February 27, 2016 by Michal Necasek

A few days ago my almost new (i.e. not quite 25 years old) Roland LAPC-I arrived. It’s essentially a MT-32 synth on a stick. I plugged it into a Pentium board, tried playing some music and… nothing. Was it perhaps not jumpered … Continue reading →

Posted in PC hardware, Roland | 12 Comments