ALR ProVEISA DMP 4/66d
ALR's ProVEISA is a server with a floor-standing case, 10 EISA slots, and 12 half-height drive bays (half 51/4-inch, half 31/2-inch). A 300-W power supply is also appropriate for server duty. The ProVEISA provides built-in SVGA graphics with 1 MB of RAM, upgradable to 2 MB.
The dual-processor ProVEISA comes with a single floppy drive and a Texel double-speed CD-ROM drive to load Windows NT. The tested configuration included NT, 32 MB of RAM, and two Maxtor 540-MB SCSI hard drives. ALR supplied the system with a caching SCSI-2 card with 4 MB of RAM. A plastic door covers access to drive bays and user controls such as the reset button. The case locks onto its chassis, but I easily broke the lock (accidentally, through misunderstanding the key position).
The ProVEISA places each 486DX2/66 pr
ocessor on a separate plug-in card, each of which takes an EISA slot. The two processor cards sit side by side with direct processor control and communication going through two sets of directly wired connectors. Each processor gets its own 512-KB RAM cache in an effort to minimize competition between the two processors for access to main memory.
Compaq ProLiant 2000
Compaq's ProLiant 2000 is a full-fledged server with lots of reliability and usability features, accounting for the $15,000 and $20,000 prices of the two test configurations (dual 50-MHz 486DX and dual 66-MHz Pentium processors, respectively). Reliability features include error-correcting memory, Compaq's Smart SCSI drive array controller, hot-swapping hard drives, and built-in SNMP-compatible system diagnostics. The SCSI controller can be configured for RAID, although I didn't take advantage of it in testing.
Compaq's Insight system management software works with the hardware to catch problems before they become disasters. The Wi
ndows-based software is easy to use and flexible in setting up server management functions. CD-ROM-based start-up software guides you through installation and configuration. Other features include Compaq's 32-bit EISA combination Ethernet/Token Ring network card and a double-speed CD-ROM drive.
Inside the big tower case are six available EISA expansion slots out of a total of eight. There are four processor slots, although the ProLiant 2000 has the power and cooling abilities to support only two. It uses the same motherboard as the ProLiant 4000, which can take four processors.
The ProLiant TriFlex architecture provides separate 64-bit processor, 128-bit memory, and 32-bit I/O buses, with a buffering bus controller between them that allows concurrent memory access by both system and I/O processors most of the time (70 percent, according to Compaq).
VTech Platinum SMP 486DX2/66 dual
VTech's dual-processor Platinum is a desktop system, aimed initially at software developers working on MP
applications and running NT-based workstation applications once they become available. Besides good performance, the VTech also has an exceptionally low price: $3999 with 16 MB of RAM, a 527-MB IDE hard drive, a double-speed CD-ROM drive, VL-Bus (VESA local bus) graphics, a 15-inch color display, and Windows NT.
The system combines two VL-Bus expansion slots with standard ISA slots. The MP daughtercard, however, takes one VL-Bus slot. The Platinum also provides built-in IDE and SCSI-2 connections, as well as high-speed serial (16550) and parallel (ECP [extended capabilities port]) ports.
The Platinum has a standard motherboard configuration with an optional plug-in card to support the second processor. The motherboard processor is installed in a ZIF (zero insertion force) socket and can be upgraded to a Pentium OverDrive chip. Both SCSI and IDE interfaces are provided standard. The dual processors communicate through the VL-Bus and the proprietary processor socket.
As with the ALR and Co
mpaq systems, the Platinum SMP design is 100 percent symmetrical; either processor can handle any task, including hardware interrupts, thanks to two Intel APICs (advanced programmable interrupt controllers). The Platinum takes a minimalist approach to multiprocessing by providing no separate secondary cache on the MP plug-in card. Both CPUs share the same 256-KB writeback cache. Even so, the Platinum provided excellent throughput results in my tests.
Photograph: ALR ProVEISA DMP 4/66d
Each 486DX2 chip sits on a circuit card (outlined) in an extended EISA slot with a 512-KB RAM cache. The two CPUs communicate via two ribbon cables.
Photograph: Compaq ProLiant 2000
Each of two special processor cards (outlined) holds a 66-MHz Pentium with a 256-KB external cache.
Photograph: VTech Platinum SMP 486DX2/66 dual
The motherboard holds a 486DX2; an optional card holds a second matching CPU (two chips outlined).
A Trio of Dual-Processor Systems
