The following values are used to set the PC/AT CMOS Table: Drive 420AT 850AT Cylinder 1010 1647 Heads 16 16 Sectors 51 63 Write Precomp 65535* 65535* Landing Zone 1010 1647
*= The Quantum Trailblazer does not require Write Pre compensation, your CMOS setting should be set to reflect that this feature is not enabled. A value of 65535 is a number that many BIOS manufactures use to disable this feature if the value 'none' is not present.
The Trailblazer 420/850AT has three drive mode jumper options; DS, SP and CS.
The SP jumper is only used when the second drive in a two drive
configuration does not support DASP. DASP (Drive active / drive
1 present) is a CAM (Common Access Method) defined signal that
indicates the presence of a second drive, DASP is used during
power on initialization and after a reset. Prior to this definition,
products were introduced which did not utilize this method to
detect the presence of a second drive. The SP jumper is only used
on the MASTER drive, with the DS jumper, when the second drive
does not support DASP.
The CS (Cable Select) jumper is only used in systems that support this feature. Cable Select allows for each IDE disk drive to be jumped the same and the position on the cable determines the ID. This requires special cable and both drives on the interface would have to support this feature.