SCSI Command Queuing and Tagged Command Queuing (TCQ)
SCSI (Small Computer System Interface) is a standard interface used for connecting peripheral devices such as hard drives, tape drives, and optical drives to computers. SCSI Command Queuing and Tagged Command Queuing (TCQ) are two related features of the SCSI protocol that improve disk drive performance.
SCSI Command Queuing is a feature that allows multiple commands to be sent to a SCSI device at the same time, regardless of the order in which they were received. The device then reorders the commands based on its own internal algorithm, which can lead to faster and more efficient use of the drive's resources.
Tagged Command Queuing (TCQ) is a specific implementation of command queuing that allows the host computer to assign a tag or identifier to each command it sends to the device. The device then uses these tags to prioritize and reorder the commands, which can lead to even better performance gains.
By using SCSI Command Queuing and TCQ, SCSI devices can handle multiple input/output (I/O) requests simultaneously, resulting in improved performance and reduced latency. This is particularly useful in high-performance computing environments where many I/O requests are generated simultaneously, such as in databases or multimedia applications.
Advanced SCSI Features and Functionality
SCSI (Small Computer System Interface) is a standard interface used for connecting peripheral devices such as hard drives, tape drives, and optical drives to computers. Advanced SCSI features and functionality refer to the additional capabilities that SCSI devices can offer beyond basic data transfer.
Here are some of the advanced SCSI features and functionality:
- SCSI Command Queuing and Tagged Command Queuing (TCQ): As explained earlier, these features allow the SCSI device to handle multiple I/O requests simultaneously, leading to improved performance.
- Synchronous Data Transfer: This feature allows the device to synchronize the transfer of data with the host computer's clock signal, reducing the likelihood of data errors and improving overall performance.
- Disconnect/Reconnect: This feature allows the SCSI device to temporarily disconnect from the host computer while data is being transferred, freeing up the host's bus for other devices. The device can then reconnect when it is ready to transfer more data.
- Scatter/Gather: This feature allows the device to read or write data from multiple non-contiguous memory locations in a single I/O operation, reducing the need for multiple data transfers and improving efficiency.
- Asynchronous Event Notification (AEN): This feature allows the device to report certain events to the host computer, such as the completion of a task or the occurrence of an error.
- Command Retry: This feature allows the device to automatically retry failed commands, reducing the need for manual intervention and improving overall reliability.
- Domain Validation: This feature allows the SCSI host to verify that a SCSI device is connected to the correct SCSI domain and avoid potential data corruption caused by misconfiguration.
Form Factor and Interface Compatibility
Form factor and interface compatibility are important considerations when selecting a hard drive. They determine the physical size and shape of the drive, as well as its compatibility with different computer systems and interfaces.
The form factor refers to the physical size and shape of the hard drive. It is important to ensure that the drive is compatible with the computer system in which it will be installed. The most common form factors for hard drives are 3.5-inch and 2.5-inch.
The 3.5-inch form factor is typically used in desktop computers, servers, and other larger computer systems. The 2.5-inch form factor is used in laptops, notebooks, and other smaller portable devices. It is important to note that while 3.5-inch hard drives are physically larger than 2.5-inch drives, they typically offer higher storage capacities and faster performance.
Interface compatibility refers to the type of interface used to connect the hard drive to the computer system. The most common interface types for hard drives are SATA, SAS, and SCSI.
SATA (Serial ATA) is the most common interface type used in desktop and laptop computers. It offers fast data transfer rates and is compatible with a wide range of computer systems.
SAS (Serial Attached SCSI) is a high-performance interface used in enterprise-level storage systems. It offers faster data transfer rates than SATA and is designed to handle heavy workloads.
SCSI (Small Computer System Interface) is an older interface type that is still used in some legacy systems. It is typically used in enterprise-level storage systems and offers high performance and reliability.
When selecting a hard drive, it is important to ensure that the drive is compatible with the computer system in which it will be installed. This includes checking the form factor and interface compatibility of the drive.
- Manufacturer: HP
- MPN: BD3008A4B6
- Type: Internal Hard Drive
- HDD Type: Ultra-320 SCSI
- SKU: BD3008A4B6
- Capacity: 300 GB
- Form Factor: 3.5 inch
- External Data Transfer Rate: 320 MBPS
Dimension and Weight
- Width : 4 Inch
- Depth : 5.8 Inch
- Height : 1 Inch
- Weight : 1.52 Lbs
- Spindle Speed: 10000 RPM
- ProLiant BL Series: BL20p G1, BL20p G2, BL20p G3, BL25p, BL40p, BL45p G1, BL60p
- ProLiant CL Series: CL1850, CL380
- ProLiant DL Series: DL360 G1, DL360 G2, DL360 G3, DL360 G4, DL360 G4p, DL380 G1, DL380 G2, DL380 G3, DL380 G4, DL385 G1, DL560, DL580 G1, DL580 G2, DL580 G3, DL585 G1, DL590, DL740, DL760
- ProLiant ML Series: ML330 G1, ML330 G2, ML330 G3, ML350 G1, ML350 G2, ML350 G3, ML350 G4, ML370 G1, ML370 G2, ML370 G3, ML370 G4, ML530 G1, ML530 G2, ML570 G1, ML570 G2, ML570 G3, ML750
About Refurbished Products
ALLHDD guarantees that the products will not have defects in material that will affect the product's functionality during the Standard Warranty Period. The warranty period starts when the merchandise/items from our warehouse.
What does ALLHDD.Com warranty cover?
30-days to 3 years warranty:
Replacement or refund. In the case of material defects, we will try to replace the product first. The product will be replaced before the expiration of the original warranty. For any failure of hardware, if we cannot process the replacement of the product(s)/model(s), we will refund the original selling/invoiced price. The shipping costs and sales tax, if any, are non-refundable. ALLHDD retains the right to decide whether the item(s) will process for replacement or refund.
What is not covered by our warranty?
The reason why our warranty does not cover any problem caused by the following conditions:
(a) misuse of hardware; accidental damage; carelessness product(s) damage; shock; temperature beyond the specification of any product; faulty installation; operation; modification of goods;
(b) any misuse outside the instructions in the user manual for any specific product;
(c) damaged caused by other hardware or equipment. The warranty will void if the item is returned with physical damage, damage to the retail box, removed from the box, counterfeit labels/labelled by them, or any modifications of internal and external covers. Data loss or damages to any other equipment we do not cover by our offered warranty.
What is the Manufacturer/Brand Warranty?
In general, a manufacturer's warranty service/support is a written guarantee to the buyer of a product. Its terms assure the replacement or repair of the product, if necessary, within a specified period after the purchase (2-5 years depending on the brand/manufacturer). It is typically included in the price of the product. Products are brand new and sealed and the original manufacturer box is complete with the Manufacturer's genuine warranty. For most of the brand new/retail products that come with the manual and box, exceptions may apply (i.e., Cisco, Juniper Networks).
For the server parts (i.e., Dell, HPE) to get Full coverage of the warranty server must have a full 3- 5 years warranty. However, ALLHDD.COM will cover the warranty duration if any Manufacturer doesn't support the advertised warranty and there is no refund for those.
Final Sale items are non-returnable/refundable in any situation. Any question? please ask our team before the shipment.
We can provide additional warranty service/support for any product you purchase from us if you need additional warranty coverage before finalizing the order from ALLHDD.Com. You need to ask in live chat/help or call us for more information.
Individual product warranty mentioned on each item product description page/detail page.
Free Technical support on purchased items, our expert consultancy over the phone, by email, by live chat, or by remote login.
Shipping Options and Estimated Delivery Time
UPS Shipping Options:
FREE UPS® Ground (Free shipping to all orders for 48 states!)
Estimated delivery time: 4-7 business days
UPS 3 Day Select®
Estimated delivery time: 3 business days
UPS 2nd Day Air®
Estimated delivery time: 1-2 business days, Delivery by 10:30 AM or 2:00 PM
UPS Next Day Air® Standard Overnight
Estimated delivery time: Overnight 2-5 PM, Standard Overnight Delivery.
UPS Next Day Air® - Priority Overnight
Estimated delivery time: Overnight Delivery (Next Business Day) Delivery by 10:30 AM or 12:00 PM
UPS Next Day Air® First Overnight - Early A.M
Estimated delivery time: Overnight 8:00 AM, Early morning, overnight delivery for your time-critical shipments.
UPS® First Overnight - Saturday
Estimated delivery time: Overnight 8:30 AM – Saturday
FedEx Shipping Options:
Estimated delivery time: (4–7 business days in the contiguous 48 states)
*For residential delivery via FedEx Ground use FedEx Home Delivery®
Estimated delivery time: 4−7 business days, based on the distance to the destination.
FedEx Express Saver®
Estimated delivery time: 3 business days (by 4:30 PM to U.S. businesses; by 8:00 PM to residences)
Available throughout all 50 states (except Hawaii and Alaska)
Estimated delivery time: 2 business days (by 4:30 PM to U.S. businesses; by 8:00 PM to residences)
Available throughout all 50 states
FedEx Standard Overnight®
Estimated delivery time: Next-business-day (by 4:30 PM to U.S. businesses and by 8:00 PM to residences)
Available throughout all 50 states (Hawaii is outbound only)
FedEx Priority Overnight®
Estimated delivery time: Next-business-day (by 10:30 PM to U.S. businesses, noon to most residences)
Available throughout all 50 states
FedEx First Overnight®
Estimated delivery time: Next-business-day (by 8:30 or 9 AM to most areas)
Available throughout all 50 states
Worldwide Shipping Options:
UPS®/FedEx® International Economy
Estimated delivery time: 4-7 business days
UPS®/FedEx® International Priority
Estimated delivery time: 2-4 business days
UPS®/FedEx® Ground Shipping Canada
Estimated delivery time: 5-8 business days
- The processing of orders with Ground Shipping can take up to 24-48 hours. But we try to process all orders the same day.
- We are not responsible for weather problems that may affect the delivery of goods by carriers. We cannot guarantee the exact delivery time, regardless of the carriers' claims.
- If you have any specific delivery time requirements, please contact our customer support and someone from our customer service team will be able to help you.
- You can estimate the shipping cost from the products detail page, also available on the checkout page
- The shipping cost depends on box dimensions, weight, and zip/postal code
- To get a FedEx® delivery service you need to mention it on the checkout page notebox.
- For urgent shipments, please contact our customer service.
- Shipping cut off 4:00 PM (Monday-Friday) and available blind drop shipment.