DPT PM2144UW

The PM2144UW is the latest release from DPT (Distributed Processing Technology-) and aims to be a high-performance SCSI controller built for the workstation and low-end server market.
While there is a vast array of SCSI controllers available, most target a specific audience with definitive RAID or cached abilities tailored to a high-end or medium-level market.
The PM2144UW is capable of providing SCSI, SCSI-2 and SCSI-3 support as well as RAID Levels 0, 1 and 5, with rhe addition of an optional module. The add-on module comes in two forms.
the RC4040 which extends the card to full length and allows the addition of up to 64M of cache RAM, and the RC4041 which overlaps the
PM2144UW and keeps its half-length size but still provides up to 32M of cache RAM. In this configuration, the PM2144UW makes a relatively affordable Fast and Ultra Wide SCSI-2 controller with optional caching and RAID abilities available, should they be desired, at an extra cost.
A comprehensive manual and a SCSI management package called Storage Manager accompany the card. The manual details everything you’ll ever need to know about SCSI, the PM2144UW and how to set up and configure your drives.
You can schedule built-in regular diagnostics and rebuilds to fit in when you might have heavy or light system loads.
The manual also covers how to set up RAID arrays with Storage Manager and what to do in the event of a failure. Storage Manager comes in native versions for Windows 95, NT, OS/2, NetWare and various flavours of Unix, and drivers for all of these platforms are also supplied.
Once installed, settings such as RAID configurations, cache parameters and general SCSI values can be saved to the card. Current transfer statistics for throughput and cache hit/miss rates can be analysed and your drives tested with built-in diagnostic software. For large RAID arrays you can even schedule built-in regular diagnostics and rebuilds to fit in when you might have heavy or light system loads.
While the card supports both wide (16-bil) and narrow (8-bit) connections, APC used only two Quantum Fireball Fast SCSI-2 drives to test the card on the narrow port in a Pentium 133MHz system with 32M of RAM running Windows 95.
For the purposes of comparison we tested the more expensive PM2144UW against an Adaptec 2940 in the same machine. To measure the effectiveness of the card and the RC4041 Cache/RAID expansion module, we used Ziff-Davis’ WinBench 96 benchmarking software and ran the full suite of disk benchmarks.
Each test was executed three times to provide an average result for comparison Tire results showed the DPT PM2144UW outperforming the Adaptec 2940 in both the random and sequential write tests (using record sizes from 200 bytes to 4K). The PM2144UW also surpassed the Adaptec 2940 on the sequential reads; however, the Adaptec 2940 considerably outperformed the DPT PM2144UW when it came to random reads. The high weighting given to this factor in the WinBench Disk/Mix mark (used to give an indication of overall performance) put the Adaptec 2940 in first place.
When the 4M cache module was added, the DPT’s results increased dramatically for sequential write operations — as much as 200% in some cases — but only marginally for read operations. The results of this can also be seen in the Disk/Mix value shown in the table.
All of DPT’s cards have one J unique feature which tends to endear them to most users: a selection of LEDs on the card display the status of the card s operations, such as drive access, cache hits, SCSI bus scanning and, more importantly, any delectable errors.
The PM2144UW can lie purchased individually or as part of a RAID kit along with the RC4041. Stan
dard DIMMs can be used in the RC4O41 or special ECC (Error Correcting Code) DIMMs can be purchased from DPT. When using ECC RAM, DPT controllers can format supported liard drives with 528-byte sectors (as opposed to the standard 512) to create ECC checking both externally and internally, theoretically ensuring data safety over your whole I/O system.
While a somewhat expensive card for the home user wishing to buy a speedy SCSI or RAID controller, the PM2144UW is a relatively inexpensive solution for the small to medium server and provides all the software and manuals needed to configure the card for either environment.