Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc. Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc.
Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc. Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc.
Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc. Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc.
Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc.
Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc.
Seagate Cheetah (ST3146855LW) 146GB, 15000RPM, 3.5" SCSI Internal Hard Drive - Anand International Inc.

Seagate

Seagate Cheetah 15K.5 ST3146855LW – 146.8GB Ultra320 SCSI LVD 68-Pin | 3.5" LP | 15,000 RPM | 16MB Cache | Enterprise HDD

$599.95
Tax included.

Brand New, Factory Sealed | In Stock | Bulk Orders Available

The Seagate Cheetah 15K.5 ST3146855LW is a 146.8GB Wide Ultra320 SCSI LVD 68-pin 3.5" Low-Profile enterprise hard drive spinning at 15,000 RPM with a 16MB multi-segmented cache buffer. The fifth-generation Cheetah 15K — and the first hard drive to break the 100 MB/s sustained transfer rate barrier — the Cheetah 15K.5 achieves a 3.5ms average read seek time, 2.0ms average latency, and sustained throughput of 73–125 MB/s across 2 discs and 4 heads using perpendicular magnetic recording (PMR) at 75GB per platter. MTBF is rated at 1,400,000 hours. The Ultra320 SCSI interface delivers up to 320 MB/s external transfer rate.

Seagate's second-generation Background Media Scan (BMS) proactively corrects incipient media errors during idle time before data is lost. Idle Read After Write (IRAW) verifies during idle time that data in the drive buffer was properly written. The 15K.5 delivers 30% more I/Os per second and over 20% faster response time than 10K drives, enabling higher system throughput with fewer drives. A 5-year warranty and non-recoverable error rate of 1 sector per 10^16 bits reflect the drive's Tier 1 enterprise design intent.

Key Specs at a Glance:

  • Capacity: 146.8GB
  • Interface: Wide Ultra320 SCSI LVD — 68-pin (LW)
  • Speed: 15,000 RPM
  • Cache: 16MB Multi-Segmented
  • Discs: 2 | Heads: 4
  • Recording: Perpendicular Magnetic Recording (PMR) — 75GB/platter
  • Avg Seek: 3.5ms (read) / 4.0ms (write)
  • Track-to-Track Seek: 0.2ms (read) / 0.4ms (write)
  • Average Latency: 2.0ms
  • Internal Transfer Rate: 960–1,607 Mbit/s (89–150 MB/s formatted)
  • Sustained Transfer Rate: 73–125 MB/s
  • External Transfer Rate: 320 MB/s (Ultra320 SCSI)
  • Idle Power: 14.2W | Active: 17.6W
  • MTBF: 1,400,000 hours
  • Non-recoverable Error Rate: 1 per 10^16
  • Form Factor: 3.5" LP | 1" height
  • Weight: ~1.85 lbs
  • Alt P/N: 9Z2005-005
Specifications

Manufacturer: Seagate

  • Series: Cheetah 15K.5 (fifth-generation 15K)
  • Model: ST3146855LW
  • Alternate Part Number: 9Z2005-005
  • Note: ST3146855LC = 80-pin SCA-2 hot-swap variant | ST3146855SS = 3Gb/s SAS variant | ST3300655LW = 300GB same family | ST3146857SS = Cheetah 15K.7 (next generation)
  • Formatted Capacity: 146.8GB
  • Bytes Per Sector: 512
  • Interface: Wide Ultra320 SCSI LVD — 68-pin
  • Spindle Speed: 15,000 RPM
  • Cache: 16MB Multi-Segmented
  • Discs: 2
  • Heads: 4
  • Recording: Perpendicular Magnetic Recording (PMR) — 75GB/platter
  • Internal Transfer Rate: 960–1,607 Mbit/s
  • Internal Formatted Transfer Rate: 89–150 MB/s
  • Sustained Transfer Rate: 73–125 MB/s
  • External Transfer Rate: 320 MB/s (Ultra320 SCSI)
  • Average Read Seek: 3.5ms (typical)
  • Average Write Seek: 4.0ms (typical)
  • Track-to-Track Read Seek: 0.2ms
  • Track-to-Track Write Seek: 0.4ms
  • Average Latency: 2.0ms
  • Idle Power (SCSI): 14.2W
  • Active Power (SCSI): 17.6W
  • MTBF: 1,400,000 hours
  • AFR: 0.62%
  • Non-recoverable Error Rate: 1 per 10^16
  • Background Media Scan (BMS): 2nd generation
  • Idle Read After Write (IRAW): Yes
  • 3D Defense System: Yes
  • S.M.A.R.T.: Yes
  • SeaTools DST: Yes
  • Warranty: 5-year limited
  • Form Factor: 3.5" Low-Profile | 1" height
  • Dimensions: 5.7" D × 4.0" W × 1.0" H
  • Weight: ~1.85 lbs
  • Drive Type: Internal Enterprise Ultra320 SCSI HDD — 68-pin Wide Cable
Product Features

Brand new, factory sealed 3.5" Low-Profile Ultra320 SCSI LVD 68-pin enterprise hard drive

  • 146.8GB formatted capacity
  • Interface: Wide Ultra320 SCSI LVD — 68-pin (LW)
  • Speed: 15,000 RPM
  • Cache: 16MB Multi-Segmented
  • Discs: 2 | Heads: 4
  • Recording: Perpendicular Magnetic Recording (PMR) — 75GB per platter
  • Internal Transfer Rate: 960–1,607 Mbit/s
  • Internal Formatted Transfer Rate: 89–150 MB/s
  • Sustained Transfer Rate: 73–125 MB/s
  • External Transfer Rate: 320 MB/s (Ultra320 SCSI)
  • Average Read Seek: 3.5ms | Average Write Seek: 4.0ms
  • Track-to-Track Read Seek: 0.2ms | Track-to-Track Write: 0.4ms
  • Average Latency: 2.0ms
  • Idle Power: 14.2W (SCSI) | Active Power: 17.6W
  • MTBF: 1,400,000 hours
  • AFR: 0.62%
  • Non-recoverable Error Rate: 1 sector per 10^16 bits read
  • Background Media Scan (BMS) — 2nd generation
  • Idle Read After Write (IRAW)
  • 3D Defense System
  • S.M.A.R.T. monitoring
  • SeaTools Drive Self-Test (DST)
  • 5-year limited warranty
  • Form Factor: 3.5" Low-Profile | 1" height
  • Dimensions: 5.7" D × 4.0" W × 1.0" H
  • Weight: ~1.85 lbs
  • Alt P/N: 9Z2005-005
Compatibility

Requires a Wide (16-bit) Ultra320 SCSI host bus adapter (HBA) with LVD support. The 68-pin connector uses a standard Wide LVD SCSI cable. Compatible with Ultra160 and Ultra2 SCSI hosts in LVD mode at degraded speeds. The ST3146855LW is the 68-pin Wide cable variant. The ST3146855LC is the 80-pin SCA-2 hot-swap variant of the same drive. The ST3146855SS is the 3Gb/s SAS variant. The ST3300655LW is the 300GB model in the same Cheetah 15K.5 family. The ST3146857SS is the next-generation Cheetah 15K.7.
Shipping & Returns
  • Free Shipping: We currently offer free Economy Shipping within the continental U.S. with no minimum order required. Expedited shipping is available at standard carrier rates.
  • Same-Day Shipping: Order placed before 2PM PST will ship the same day. Orders received after this time will ship the following business day.
  • Hassle-Free Returns: If you're not completely satisfied with your purchase, simply return it within 10 days for a hassle-free refund or exchange.

146.8GB Ultra320 SCSI LVD 68-Pin Cheetah 15K.5 15,000 RPM 3.5ms Seek 125 MB/s Sustained 16MB Cache 1.4M Hour MTBF Alt P/N: 9Z2005-005 Factory Sealed

The first drive to break 100 MB/s sustained transfer rate — Seagate's Cheetah 15K.5 ST3146855LW delivers 3.5ms seek, 125 MB/s peak sustained throughput, and perpendicular recording at 75GB/platter in a 146.8GB Ultra320 SCSI 68-pin enterprise platform

The Cheetah 15K.5 (ST3146855LW) is the 68-pin Wide cable variant of Seagate's fifth-generation 15,000 RPM enterprise drive — and the first hard drive in history to exceed 100 MB/s sustained transfer rate, achieving up to 125 MB/s via perpendicular magnetic recording at 75GB per 2.6-inch platter. The 15K.5 delivers 30% more IOPS and over 20% faster response time than 10K drives, making it Seagate's recommended solution for Tier 1 enterprise, database, and high-frequency transaction applications. Second-generation Background Media Scan and Idle Read After Write proactively protect data integrity during idle periods. The LW suffix designates the 68-pin Wide cable interface; the LC variant uses an 80-pin SCA-2 hot-swap connector. The Cheetah 15K.5 carries a 5-year limited warranty and 1,400,000-hour MTBF.

First Drive to Break 100 MB/s Sustained — Perpendicular Recording at 75GB/Platter

The Cheetah 15K.5 was the first hard drive to exceed 100 MB/s sustained transfer rate, reaching up to 125 MB/s outer-zone throughput — a 30% improvement over the preceding Cheetah 15K.4 and enabled by Seagate's first deployment of perpendicular magnetic recording (PMR) in the Cheetah family. PMR stores data bits vertically on the platter surface, achieving 75GB per 2.6-inch disc and an internal transfer rate spanning 960–1,607 Mbit/s (89–150 MB/s formatted).

15,000 RPM — 3.5ms Read Seek, 0.2ms Track-to-Track, 2.0ms Latency

At 15,000 RPM, the Cheetah 15K.5 achieves a 3.5ms average read seek time, 0.2ms track-to-track read seek, and 2.0ms average rotational latency — delivering 30% more IOPS and over 20% faster response time than 10K RPM drives. This enables the same I/O performance to be met with fewer physical drives, reducing rack space, power, and total cost of ownership in dense enterprise storage environments.

Ultra320 SCSI — 320 MB/s External Rate | 2nd-Gen BMS | IRAW | 3D Defense System

The Ultra320 SCSI LVD interface delivers up to 320 MB/s external transfer rate on a Wide (16-bit) LVD bus. Seagate's second-generation Background Media Scan proactively scans the disc surface during idle periods to detect and correct incipient defects before data loss occurs. Idle Read After Write (IRAW) verifies buffer-written data during idle time to ensure write accuracy. The 3D Defense System provides comprehensive drive, data, and diagnostic protection.

Brand New, Factory Sealed — 68-Pin LW Variant | Alt P/N: 9Z2005-005 | 5-Year Warranty

Available as brand new factory sealed units, alt P/N 9Z2005-005. The ST3146855LW is the 68-pin Wide cable (LW) variant of the Cheetah 15K.5 146.8GB. Not to be confused with the ST3146855LC (80-pin SCA-2 hot-swap variant), ST3146855SS (3Gb/s SAS variant), ST3300655LW (300GB model, same family), or ST3146857SS (Cheetah 15K.7 — next generation).

Frequently Asked Questions

Frequently asked questions for SCSI, including information on usage, configuration, and compatibility.

1. What is a SCSI hard drive?

A SCSI (Small Computer System Interface) hard drive is a legacy enterprise storage device that connects using parallel ribbon cables. SCSI was widely used in servers, workstations, and storage arrays before newer technologies like SAS and SATA became standard.
2. What systems are SCSI hard drives compatible with?

SCSI drives are designed for older servers, RAID controllers, and storage arrays that have SCSI interfaces. They are commonly used today to maintain or repair legacy IT infrastructure.
3. What’s the difference between SCSI and SAS?

SCSI uses parallel communication and bulky ribbon cables, with speeds up to 320 MB/s. SAS (Serial Attached SCSI) is the modern successor, offering serial communication, smaller connectors, dual-port redundancy, and speeds up to 24 Gb/s.
4. Can SCSI hard drives still be used in modern systems?

Most modern computers don’t have SCSI ports. To use a SCSI drive, you’ll need a compatible SCSI controller card or an external enclosure designed for parallel SCSI.
5. What capacities are available for SCSI hard drives?

SCSI hard drives were typically available in capacities ranging from a few gigabytes to several hundred gigabytes. Larger capacities are rare compared to modern SATA and SAS drives.
6. Are SCSI hard drives hot-swappable?

Yes, many SCSI drives used in enterprise servers were hot-swappable when paired with a compatible RAID backplane or enclosure. This allowed replacement without shutting down the system.
7. Why are SCSI hard drives still used today?

SCSI hard drives remain important for maintaining legacy servers, specialized equipment, and industrial systems where upgrading to newer storage technologies isn’t possible or practical.