Category Archives: Intel

Undefined Isn’t Unpredictable

The other day I discovered that 32-bit FreeBSD 11.2 has strange trouble running in an emulated environment. Utilities like ping or top would just hang when trying to print floating-point numbers through printf(). The dtoa() library routine was getting stuck … Continue reading

Posted in AMD, Development, Documentation, Intel | 15 Comments

Does (E)IP Wrap Around in 16-bit Segments?

The 8086/8088 is a 16-bit processor and offsets within a 64K segment always wrap around. If a one-byte instruction at offset FFFFh is executed on an 8086, execution will continue at offset 0. This is simply a consequence of the … Continue reading

Posted in 386, 8086/8088, Intel, x86 | 9 Comments

IBM AIX for IA64 (Itanium) aka Project Monterey Runs Again!

(This is a guest post by Antoni Sawicki aka Tenox) Project Monterey was an attempt to unify the fragmented Unix market of the 90s in to a single, cross vendor Unix OS that would run on the upcoming Intel Itanium … Continue reading

Posted in IBM, Intel, SCO, UNIX | Tagged , , , , , , , | 10 Comments

XMVM Surgery

Last week I was prompted to take a look at the Intel Code Builder compiler from 1991, a 32-bit compiler targeting 386 extended DOS and shipping with its own DOS extender. It is what one might call an extremely obscure … Continue reading

Posted in 386, Development, Intel, PC history, Software Hacks | 10 Comments

The IBM PC, 41 Years Ago

No, the OS/2 Museum does not have either a time machine or difficulty doing basic math. As of this writing, it is August 2021 and the IBM PC was announced in August 1981, 40 years ago. But in August 1980, … Continue reading

Posted in 8086/8088, BIOS, DOS, IBM, Intel, PC hardware, PC history | 60 Comments

Nobody Expects…

…the Spanish Inquisition! Well, that too, but also nobody expects that a bland, run-of-the mill Novell NE2000 NDIS driver would crash/hang just because it runs on 486 or later CPUs. I wanted to try the “basic” DOS redirector shipped with … Continue reading

Posted in 486, Bugs, Intel, Microsoft | 6 Comments

8237A DMA Page Fun

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 | 3 Comments

Nehalem and 4 Gbit DDR3

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 | 8 Comments

The Phantom Intel GM47 Chipset

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…

…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