2024-12-23

scsi drive

Is it normal for a 10,000 RPM Serial ATA or SCSI drive to run hot?

DATARECOVERYUNION.COM01 mins

It is normal for a 10,000 RPM Serial ATA or SCSI drive to be hot when it is in operation. The reason is because the drive is rotating at an extremely fast rate, 10,000 rotations per minute. For example, while in operation, the temperature of a 10,000 RPM drive will be hotter than a 7200 RPM or 5400 RPM drive which rotates at a slower speed. Overheating can cause damage to a hard drive. Make sure that your system has adequate cooling fans.

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SCSI controller card troubleshooting with Apple Macintosh

DATARECOVERYUNION.COM03 mins

SCSI Controller Card I just installed a new hard drive, but now get intermittent lock ups on boot, error messages that I cannot read from the hard drive, or errors that show problems with the hard drive or file system. What should I explore first?

Note: This document applies to Mac OS 8.6 thru 9.x.

Some operating systems do not support all default SCSI drive features. If you are using a generic (not MAC branded) hard drive, the drive may behave erratically as it may not be optimized for the operating system. If you are seeing these symptoms, find out if SCSI Mode Page editing is supported by the SCSI controller. Disable Initiate Synchronous Negotiation and Disconnect/Reconnect if available at the SCSI controller. Also Unit Attention. Run the Media Verify option from the SCSI controller utilities, to verify data integrity on the hard drive.

These features may not be available at all SCSI controllers. Third party software may be needed to set the hard drive SCSI Mode pages for these features. You will need a SCSI Mode Page Editor tool. See your system manufacturer for SCSI tools.

Isolate the suspect drive to the only device on the controller and retest. Replace the data cable, devices, or external terminators. Verify that both ends of the SCSI bus are terminated. If the hard drive has an option for Termination Power–use it. Or confirm that the SCSI controller supports/supplies bus Termination Power. This is especially important with long cable runs or when using more than one SCSI device.

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How to terminate A SCSI hard drive?

DATARECOVERYUNION.COM04 mins

SCSI Hard Drive With today’s high speed hard drives combined with long cable runs, only use high quality ‘twisted pair’ cable and external active (cable end) terminators. Active termination boosts data integrity and reliability. With active termination, a 110-ohm resistor on each signal line connects to a voltage regulator. The regulator ensures signal quality over the entire length of the SCSI bus. This reduces under and overshoot signals typically found on passive resistor termination schemes.

Passive termination draws its electrical power from the SCSI host adapter. A 220/330-ohm resistor is used to provide the necessary impedance to prevent the data signal from ‘reflecting’ back. Fluctuations in termination power (or failing cables) can show up as error symptoms in the drive, yet do not originate there. In general we recommend you enable SCSI Termination Power if available.

  • Maxtor (and Quantum) SCSI disk drives have either onboard active termination (jumpers). Older drives (circa 1994) enable active termination by two removable (10-pin) termination resistors. Some use passive termination with three removable (8-pin) terminating resistor packs. Seagate does not supply terminating resistor packs for older drives.
  • SCSI Single Ended Hard drives using active onboard termination have a jumper setting labeled ‘TE’ to control the termination setting.
  • All Quantum Single-Ended SCSI drives ship defaulted to provide SCSI Termination Enable.
  • SCSI LVD(low voltage differential) drives do not supply SCSI Termination Enable. Refer to the drive configuration guides for proper setting of this feature.Notes:
    1. Some Quantum SCSI disk drives are available in both Single-Ended and LVD versions. Specifically, the Atlas III and Viking II drives offer both types of termination. Atlas III Narrow (50 pin) drives are Single-Ended, while the Wide (68 pin) and SCA (80 pin) versions are LVD models. Viking II Wide drives are available in both SE and LVD models. The part number for an SE drive will contain “W”, and the LVD will contain a “L” (e.g. PX09L011 would be LVD). All Viking II SCA drives are LVD models. All fifty pin Quantum SCSI drives are all SCSI Single-Ended.
    2. LVD cables and SCSI bus terminators can be purchased from TMC (The Mate Co.) or a local retailer.
    3. Use due diligence when installing or adding SCSI devices. Unlike most electronic devices, SCSI may operate if improperly terminated, but performance and reliability will be seriously at risk.
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Can I boot my computer from SCSI drive?

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SCSI Drive Will my new SCSI drive boot my computer? or error message:

no ROM BIOS?

The drive will need to be partitioned and formatted for your computer’s operating system before it can be used as the boot drive. Follow the instructions in the operating system or computer manual for installing a new hard drive and loading the operating system.

SCSI boots from BIOS. Most SCSI controllers feature on-board ROM BIOS to controll the disk drive. Older SCSI controllers may use jumpers or a start up disk to access BIOS. Enable SCSI BIOS for the active partition, C:\, to be recognized. Using more than one SCSI controller? Choose only one to start up. Typically only one active partition is allowed each drive. If BIOS has support for removable disks as hard drives, choose:All Disks. Consult your SCSI controller or system guides.

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