Deskpro EN - 01 May 1999

500MHz Intel Pentium III processor debuts

Hear ye, hear ye—500MHz Pentium III systems have arrived. Last month, I reviewed Compaq's 400MHz Celeron desktop PC (see "Deskpro EN," April 1999); this month, I review the 500MHz Pentium III Deskpro EN. This enterprise-level desktop PC provides power for business professionals.

You can easily remove the system's case. A vertical expansion backplane separates the motherboard on the left side of the system from the power supply, hard disk, 3.5" disk drive, and CD-ROM drive on the right side of the system. The motherboard houses the Accelerated Graphics Port (AGP) slot, and the backplane houses two PCI slots and two shared PCI/ISA slots. To add and remove cards, you raise the backplane by lifting two levers on the front and rear of the board. To work with the slots on the bottom of the backplane, you must remove a large power cable that connects to the rear of the backplane.

With the Ethernet card installed, the system has only three open expansion slots and only one internal or external full-size drive bay available. A system with so much processing power needs more versatility. To incorporate additional expansion slots, Compaq might want to consider integrating Ethernet capabilities onto the motherboard. However, the company says it isn't pursuing this option, because corporations prefer to standardize on particular NICs to reduce support costs. In addition, standard desktops usually aren't candidates for expansion devices.

The motherboard has a 100MHz system bus and houses integrated sound and three DIMM slots. I find the system's memory expansion options limiting. Because a 500MHz processor gives you a lot of power, limiting the system to three DIMM slots reduces performance. Although the system supports as much as 768MB of Synchronous DRAM (SDRAM), you must use the most expensive DIMMs available (i.e., 256MB).

The Deskpro EN's Pentium III is faster than Intel's previous processors and better able to manipulate high-end 3-D graphics. The processor is available with clock speeds of 450MHz or 500MHz. The workstation version has a 512KB Level 2 cache, and the server version (the Xeon) has a 512KB to 2MB Level 2 cache.

The Pentium III offers specialized code for targeting specific processes. The processor has about 70 new single-instruction, multiple-data (SIMD) streaming extensions for floating-point datatypes. These extensions render 3-D images quickly. Rendering often involves performing numerous floating-point calculations repeatedly (such as when transforming several vertices). The Pentium III uses SIMD instructions to process these calculations simultaneously and thus save time.

According to Intel, SIMD extensions boost system-level performance by 5 to 10 percent. Improved cache management lets the Pentium III provide increased Internet and TCP/IP performance and benefits memory-intensive and media applications such as databases, telephony, voice recognition, streaming media, and compression software.

Few applications can currently take advantage of the Pentium III's abilities. However, I expect that Pentium III processors will become more prevalent by the end of the year and software vendors will soon introduce applications that use the new SIMD instructions.

To test the Deskpro EN's performance, I ran AIM Technology's benchmark tests. The system's WNT Peak Performance score was 899.4 jobs per minute, and its Sustained Performance score was 248 jobs per minute. This machine is as fast as any single-processor system I've tested.

The 500MHz Pentium III Deskpro EN performs well. The system is faster than a 400MHz Pentium II system but not so fast that you need to run out and get one today. However, if you buy the processor for its integrated SIMD instructions, you'll appreciate its speed.