Category Archives: Intel

If you ENTER, you might not LEAVE

Posted on June 7, 2013 by Michal Necasek

I’ve recently spent some time debugging curious hangs/aborts in two more or less exotic operating systems, Plan 9 and QNX 4.25. Both turned to be caused by the same innocuous-looking BIOS change, even though the circumstances were somewhat different and … Continue reading →

Posted in Intel, x86 | 9 Comments

The Pin N33 Mystery and the History of Slockets

Posted on April 21, 2013 by Michal Necasek

The Ultimate Museum PC (UMPC) is a dual Slot 1 based system. Fast Slot 1 based Pentium III processors turned out to be extremely difficult to find (especially at non-ridiculous prices like $200 per CPU). The current 850MHz processors are … Continue reading →

Posted in Intel, PC hardware | 4 Comments

The Tualatin Story

Posted on April 6, 2013 by Michal Necasek

While researching the Ultimate Museum PC it was hard to avoid the Tualatin, the final 0.13-micron incarnation of the Pentium III. With speeds up to 1.4GHz and 512KB on-chip L2 cache, a pair of PIII-S Tualatins should provide decent oomph. … Continue reading →

Posted in Intel, PC hardware | 15 Comments

The Ultimate Museum PC, Continued

Posted on March 9, 2013 by Michal Necasek

Two weeks after discussing the Ultimate Museum PC, the first “new” hardware components arrived (nearly all on the same day). Chief among these are two motherboards: Supermicro P6DBE and ASUS P2B-DS. The boards are very similar, yet quite different. Just … Continue reading →

Posted in Intel, PC hardware | 12 Comments

The Ultimate Museum PC

Posted on February 27, 2013 by Michal Necasek

While the OS/2 Museum employs modern computers and virtualization heavily, sometimes there is a need for good old hardware—emphasis on good and old. A virtual machine won’t read 5¼” floppies and there’s no way to plug in a real Sound … Continue reading →

Posted in Intel, PC hardware | 31 Comments

SCO UNIX 3.2v4.0 vs. IA-32 Semantics Changes

Posted on January 25, 2013 by Michal Necasek

People noticed a long time ago that SCO UNIX 3.2v4.0 won’t boot on anything resembling modern hardware, and it won’t boot in a VM either. In a VM the results may be inconsistent across implementations, but on a physical machine … Continue reading →

Posted in 386, Intel | 6 Comments

Why Windows NT from October 1992 refuses to install on modern CPUs

Posted on October 12, 2012 by Michal Necasek

Attempting to install the October 1992 pre-release on any CPU less than about 20 years old is likely to result in the following error message: This is similar to the behavior of the official Windows NT 3.1 and 3.5 releases, … Continue reading →

Posted in Intel, NT | 15 Comments

An old idea: x86 hardware virtualization

Posted on May 13, 2012 by Michal Necasek

It is well known that virtualization of the x86 architecture is an old idea. The Intel 386 processor (1985) introduced the “Virtual 8086” (V86) mode, enabling users to run real-mode operating systems as a task within a 32-bit protected-mode operating systems. … Continue reading →

Posted in 386, Intel, Virtualization | 14 Comments