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376220-001
Service Reference Guide, dc5100
Serial and Parallel ATA Drive Guidelines and Features
4.3.2 PATA Attach Sequence Rules by Class Priority
Drives should be attached in the sequence shown for optimum performance starting at
position
1
.
*If there are three or more devices, two or more of which are hard drives, two hard drives should
be attached to the primary channel first before following the General Attach Sequence Rule.
The attach sequence rule may also be stated in table format:
✎
Cable lengths may restrict drive usage.
The rules allow for:
■
Keeping the hard drive on a separate channel to maximize drive performance until a fourth
device is added.
■
Keeping the hard drives and removable media drives on separate channels to maximize
compatibility.
■
Keeping the hard drive and the writable optical drive on separate channels to maximize
optical drive reliability.
General Attach Sequence Rule*
Sequence
Description
1
The lowest class drive—bootable hard drive recommended.
2
If only two drives, the last drive goes here; otherwise the lowest class of the
remaining drives.
3
If only three drives, attach the final drive here. If a fourth drive exists, attach the
lowest class drive here.
4
If there is a fourth drive, attach the final drive here—the drive with the highest
class number of all devices.
*If there are three or more devices, two or more of which are hard drives, two hard drives should
be attached to the primary controller first before following the General Attach Sequence Rule.
1
2
4
3
Primary
Channel*
4
1
Secondary
Channel
3
2
Device 1
Device 0
