Monthly Archives: March 2015

IBM XENIX: One Step Forward, One Step Back

A while ago I wrote about why IBM PC XENIX 1.0 can’t work on any CPU other than a 286. But not content to leave well enough alone, I attempted to patch this version of XENIX so that it would … Continue reading

Posted in 286, 386, IBM, VirtualBox, Xenix | 4 Comments

The DOS 4.0 Shell Mouse Mystery

Several years ago, I noticed that in some virtual and physical environments, the DOS Shell in both IBM’s and Microsoft’s DOS 4.0x has a very odd glitch: the mouse pointer moves, but does not register any clicks… except on scroll … Continue reading

Posted in DOS, IBM, PC hardware, PC history | 25 Comments

Do You Know These Peripherals?

After a long pause, here’s another guessing game. Do you recognize the five peripherals below? This should be very easy since the manufacturers’ names are clearly visible, only the model numbers got “lost”. This is all 1980s-1990s hardware from (obviously) … Continue reading

Posted in MIDI, Roland, Sound, Yamaha | 10 Comments

What Is DXP44Q?

Today I came across a random 1996 vintage ISA sound card (no name, made in China). The only two chips worth noting on the board are an OPTi 82C930A chip and a mysterious DXP44Q—a square chip center left, to the … Continue reading

Posted in PC hardware, Sound | 7 Comments