Manufacturer : Seagate
MPN : ST3146855LC
Type : Hard Disk Drive (HDD)
Sub-Type : Ultra320 SCSI
SKU : ST3146855LC
Capacity 146 : GB
Interface Type : Ultra320 SCSI
Connector : 80 pin HD D-SUB
SCSI Signaling Type : Low Voltage Differential LVD
Buffer Size : 16 MB
Drive Transfer Rate : 320 MBPS external / 150 MBPS internal
Seek Time : 3.5 MS Average / 6.7 MS MAX
Track-to-Track Seek Time : 0.2 MS
Average Latency : 2 MS
Spindle Speed 15000 RPM
Expansion / Connectivity
Interfaces 1 x Ultra320 SCSI - 80 pin HD D-SUB HD-80
Compatible Bays 1 x internal - 3.5 Inches
Dimension and Weight
Width : 4 Inch
Depth : 5.8 Inch
Height : 1 Inch
Weight : 1.52 LBS
About Refurbished Products
The ultra320 SCSI hard drive generation is the immediate upgrade of its predecessor, the ultra160 SCSI. The newer generation ultra320 SCSI HDD comes about as an implementation of the SCSI-3 Parallel Interface-4 (SPI-4) standards.
Over its lifetime, the SCSI standard is widely used in servers and high-end workstations. It is possible to install SCSI HDDs in a desktop PC that has one or more IDE disk drives. The IDE drive acts as the boot drive, while the SCSI hard drive provides additional storage capacity. SCSI is not commonly used in desktop PCs, although it allows the addition of a scanner and several other drives such as DVD-RAM, CD-Rs, and Zip drives to a single SCSI cable chain. USB and FireWire have gradually replaced the SCSI as alternate interfaces in the latest desktop PCs.
In-network servers, SCSI allows for the setting up of several hard drives in the RAID configuration to reduce the risk of loss of data. The configuration supports hot-swapping - the changing of hard drives while the system is still operating.
Ultra320 SCSI HDD just as the name suggests delivers 320 Mbps top speed and provides a faster bus at 80 MHz and a wider data path at 16 bit. Connections with the Ultra320 SCSI HDDs just like with SCSI devices can be daisy-chained since they have two ports - the incoming and the outgoing cables. Besides, SCSI has a strong commitment to backward compatibility to previous generations, which explains its widespread use as an I/O interface and elimination of the need for substantial investments in equipment and infrastructure. Migration to the ultra320 SCSI HDD is smooth whether it is from the Ultra160 SCSI or other generations of the SCSI standard because of backward compatibility.
The ultra320 SCSI hard drive takes on technologies such as domain validation, cyclic redundancy check, and dual-edge clocking first introduced by ultra160 SCSI. Additionally, the ultra320 SCSI hard drive introduces protocol changes and other technologies that enhance performance and support reliable data transfer speeds at 320 Mbps. We have the following ultra320 SCSI HDD options: 146GB-10K RPM, 146GB-15K RPM, 300GB-10K RPM, 300GB-15K RPM, 36GB-10K RPM, 36GB-15K RPM, 73GB-10K RPM, 73GB-15K RPM, and 18GB-15K RPM to meet your performance and storage requirements.
The standard features of the ultra320 SCSI hard drive include:
- Two-fold increase in transfer speed: The ultra320 SCSI hard drive increases the transfer rate by 100% from the previous generation at the rate of 320 Mbps. The technology allows greater transfer rates, effectively leading to greater performance in environments of extended data transfer and support for many devices on a single bus.
- Support for SCSI packet protocol: By enabling packet protocols, the ultra320 SCSI HDD helps to reduce command overhead by using dual transition (DT) data phases to transfer data, commands, and statuses rather than asynchronous phases that are generally slow. Packet protocol allows for the transfer of multiple commands in one connection as well as increased performance through minimal command overhead and maximum bus utilization.
- Quick Arbitration and Selection (QAS): the technology helps reduce control release overhead between devices at the SCSI bus. QAS is all about reducing command overhead and maximizing utilization of the bus.
- Read/Write Data Streaming facilitates the reduction of overhead associated with data transfer through the sending of a LUN Q-TAG (LQ) data stream packet, which is subsequently followed by multiple data packets. Greater write data streaming is achieved since the bus turnaround delay is eliminated between LQ and data packets.
- The flow control feature facilitates the initiator to enhance the pre-fetching of data for writes and enhance the flushing of FIFOs for reads.