The PowerPC adventure—by far the most exotic release of OS/2
In December 1995, after unexpectedly long development (but is that really unexpected?), IBM finally “shipped” OS/2 Warp, PowerPC edition. For brevity, this release will be further referred to as OS/2 PPC. Following years of hype and high expectation, the release was very low key and in fact marked the end of development of OS/2 for PowerPC. The product was only available to a limited number of IBM customers and was never actively marketed. OS/2 PPC may not even had a box, although there were nice looking official CDs.
The Hardware
OS/2 PPC only supported an extremely limited range of hardware—IBM Personal Power Series machines. Those were desktop models 830 and 850, and OS/2 PPC probably also supported the Power Series ThinkPads 820 and 850, though that can be only inferred from the fact that the graphics chipset employed by these ThinkPads was on the very short list of supported devices in OS/2 PPC.
The IBM Power Series computers were IBM’s rather short lived foray into the PowerPC-based desktop personal computer market, circa 1995-1996. The PowerPC CPU aside, the systems were very similar to Intel based hardware of that era. They were designed around the PCI bus, but also included ISA expansion slots and on-board Crystal Audio ISA PnP chips. The desktop Power Series machines were IDE based, ThinkPads used SCSI disks. The computers had standard serial and parallel ports, as well as most of typical PC hardware such as interrupt and DMA controllers. The desktops had onboard S3 864 video, ThinkPads used Western Digital flat panel chipsets. Several optional graphics cards were supported, notably Weitek P9100 based accelerators. The desktops also had onboard Ethernet chips (AMD PCnet).
The Power Series systems were closely related to certain IBM RS/6000 workstations. The RS/6000 Model 43P-7248 was nearly identical to the Power Series 850. They used the same motherboard, only the RS/6000 had on-board SCSI controller. Unlike the RS/6000 systems intended for the workstation market and running almost exclusively IBM’s AIX operating system, the Power Series systems were designed for “regular” personal computer users. The machines were supposed to run OS/2, Windows NT, AIX, or Solaris. OS/2 PPC was only semi-finished, and the Solaris for PowerPC port (version 2.5.1) was similarly short-lived. Microsoft dropped PowerPC support in 1996, not long after the Windows NT 4.0 release. Most of the Power Series systems ended up running AIX, which supported them until version 5.1. Linux also supported the Power Series to some extent. Windows NT was clearly the closest competitor of OS/2 PPC.
For this article, OS/2 PPC was installed on a Power Series 830, installed by its previous owner in a RS/6000 43P case. The CPU was a 100MHz PowerPC 604 with 256KB L2 cache, and the machine was equipped with 192MB RAM, which was the maximum it could handle. The graphics was an on-board PCI S3 Vision 864 with 2MB video memory and true color S3 SDAC. The machine was equipped with 2.1GB IDE hard drive—AIX can handle up to 8GB and Linux can utilize even larger disks, but OS/2 and NT were not happy with anything over about 2.5GB. The 830 was originally sold with either 500MB or 1GB disks and 16MB RAM. The Power Series 850 systems were equipped with 100 or 120MHz CPUs, slightly more RAM and larger disks.
The Software
OS/2 Warp, PowerPC edition was delivered on two CDs. The first CD contained the operating system and BonusPak, the second CD was an application sampler with several demo applications.
Installation was surprisingly easy and painless. The CD was bootable and there were almost no choices to make during installation—only the disk partitioning was user selectable. The PowerPC operating systems (OS/2, NT, AIX and Linux) generally did not coexist as there was no real equivalent of a boot manager and each OS wanted to install its own boot loader. The OS/2 installer re-partitioned the disk and overwrote any other operating systems. The boot partition had to be FAT. It was possible to create HPFS data partitions, but the HPFS support appeared to be somewhat unstable and likely a last-minute addition.
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