Motorola PowerStack RISC PC

High-end PowerPC Workstation Performance

Although it may come as a surprise, Motorola does make computers as well as chips, and the company's PowerStack RISC PC with a 133-MHz PowerPC 604 is probably the fastest PowerPC/Windows NT system I've seen yet. And, rumor has it, faster versions, such as a 150-MHz 604, are on the way. Motorola recently leaked information about the PowerPC 604e chip: It improves on the older 604 design by increasing its L1 cache to 32KB for instructions and 32KB for data, and raises the processor clock speed to 166 MHz. There are also other enhancements to the architecture.

Motorola's PowerStack RISC PC shows its processing prowess right out of the box with some sample programs, such as Microsoft Office 4.3 and SoftMPEG. I don't have formal benchmarks for the Motorola PowerPC, such as the BAPCo SYSmark I used for the Hewlett-Packard (HP) Vectra in the January issue. However, I was able to make a reasonable value judgment about the PowerStack: It's very fast. (See the sidebar "How Does the PowerStack Stack Up?" on page 50).

My test system had only 64MB of RAM, which is just enough to allow NT to come into its stride. When you launch applications such as Microsoft Word, the first instance takes only a few seconds to execute, and each subsequent instance comes up even faster--in less than a second--because it's cached in the system memory. There's no difference in speed whether you add another simultaneous application or kill the first one.

The PowerPC shows its muscle with multimedia applications, such as 3D rendering, morphing, and Moving Pictures Experts Group (MPEG) video files, which you can play back from CD or the hard drive if you have the appropriate software. The unit has line I/O and microphone connectors to let you attach speakers and record sound. It uses a Crystal Semiconductor Coder/Decoder (codec) chipset to provide 16-bit CD-quality sound, compatible with the PowerPC Reference Platform (PRP) and the Windows Sound System, with a Multimedia PC (MPC)-compatible sound mixer. The Motorola PowerPC supports full multimedia functionality, including full-duplex stereo, speech recognition (with software), synthesized sounds for music software and Musical Instrument Digital Interface (MIDI), and CD sampling. The company also offers its own line of 15", 17", and 21" monitors. I sampled the 17", which is capable of up to 1600 x 1200 resolution (0.28mm dot pitch).

The PowerStack is available in either a minitower or a desktop case. The only differences between the two are in the number of expansion ports and drive bays: The desktop has one Peripheral Component Interconnect (PCI) slot, one ISA slot, one combination expansion slot, and two externally accessible half-height 51Ž4" drive bays, while the minitower has two PCI, two ISA, and one combination expansion slots and three drive bays. Otherwise, the two have the same setup: They have four 72-pin single in-line memory module (SIMM) slots, a built-in 10-megabit (Mb) Ethernet (10-BaseT, 10-Base5), two serial ports, one parallel port (plus room for a second parallel port on the minitower), a keyboard/mouse, SCSI-2, a Super Video Graphics Array (SVGA) display, a floppy disk drive, and a single internal 31Ž2" hard disk bay. The desktop unit also has a SCSI-3 connector.

The minitower system is modular enough to provide easy access to critical components for upgrades and repair. The housing detaches with a single thumbscrew and two spring latches on the back. The desktop system has only two release tabs.

Special features in the PowerStack include fully integrated PCI features: 64-bit graphics from Cirrus Logic (1MB of VRAM, upgradeable to 2MB), a SCSI-2 and -3 engine, and Ethernet, all on the motherboard, as well as integrated business audio to provide an out-of-the-box network-ready solution. The 512KB L2 cache in the PowerStack is synchronous 9-nanosecond memory, which offers performance advantages over the asynchronous memory used in many Pentium-based computers. The PowerStack is fully PRP-compliant (see the sidebar "The PowerPC Platform" on page 52), which guarantees a future for it. In February, a 150-MHz processor upgrade will be available. You will be able to upgrade via a module installed in the L2 cache slot--which is also the Processor Direct Slot (PDS) upgrade socket--or through a motherboard swap. This system has no multiprocessor support, but dual- and quad-processor servers are due out in the second quarter of this year. They will be based on Motorola's own PowerPC Platform design, rather than on Groupe Bull's current one/two-way Series I and two/four-way Series MP OEM Micro Channel boards.

PowerPC performance and compatibility are increasing by leaps and bounds. Boot and startup are quick, multiple running instances of applications don't slow it, and screen redraws are lightning fast because of the unit's Diamond Viper video card. More vendors than in the past are offering PowerPC versions of their applications, so there is much more software than there was just six months ago. When Microsoft's Shell Update is released with its full 486-emulation (for PowerPC, Alpha, and MIPS), the rest of the 16-bit software world will be accessible. Graphics performance, although dependent on your adapter, is high with just the PCI video on the motherboard and can be upgraded with cards such as the Diamond Viper and the Omnicomp 3Demon.

My first impressions of the PowerStack are good: It has an excellent price/
performance value, especially if you want to apply it to multimedia, where software-based MPEG coding and decoding outperforms some hardware-based solutions. For example, SoftMPEG from Compcore offers full-screen 30 frames-per-second playback. The PowerStack works well with standard office-automation and other packages, and I can recommend this machine as a viable high-performance alternative to Intel and Alpha competitors. Motorola's target audience is Fortune 2000 MIS managers and early adopters of the Windows NT technology. The company hopes to increase the system's computer-aided design (CAD) presence with packages such as ProEngineer and MicroStation, which will appear in native versions by the end of the first quarter of this year. The PowerStack is expected to compete directly against Pentium 100-MHz/133-MHz systems, Sun SPARC 5 and 10, HP 712/715/725 (PA-RISC), and the IBM RS6000 43P.