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Intel does not recommend specific hard disk drive vendors or technology and feature implementations, however this guide will provide a brief technical explanation of the differences between using SAS or SATA Hard Drives to provide system integrators with the key information they need to determine their hard drive requirements.
To achieve a balanced setup in considering all the requirements with related costs, the checklist below may assist you in choosing between SATA and SAS Hard Drives for your system RAID.
| Note |
Vendor implementations of these features vary between drive models. (Typical MTBF, operating temperature, and operating rotational vibration vary depending on the manufacturer). Generally the high end of the feature spectrum includes enterprise-class SAS hard drives, and the low end includes desktop-class SATA drives. Enterprise-class SATA drives fall somewhere in between. | |
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Requirement |
SAS |
SATA |
|
Operational Availability |
24 hours/day - 7days/week |
8 hours/day - 5days/week |
|
Workload |
100% |
10-20% |
|
Cost Sensitivity |
Moderately sensitive to cost |
Sensitive to low cost |
|
Performance |
Latency and Seek |
5.7 msec @ 15K rpm |
13 msec @ 7200rpm (or smaller) |
|
Command Queuing and Reordering |
Full |
Limited |
|
Rotational Vibration Tolerance |
Up to 21 rads/sec/sec |
Up to 5 to 12 rads/sec/sec |
|
Typical I/Os per sec/drive |
319 |
77 |
|
Duplex Operation |
Full |
Half |
|
Reliability |
Bad Sector Recovery |
Typical time out 7-15 sec only |
Time outs up to 30 sec |
|
Misalignment detection |
Dedicated Servo and data path processors |
Single combined servo/data path processor or none |
|
Vibration Sensors |
RV Compensation Feedback Mechanism |
No RV Compensation |
|
Variable Sector Size |
Utilizes a 528 byte sector and allow the I/O controller |
Do not utilize a variable sector size (locked at 512 bytes) |
|
MTBF |
1.2M hours at 45 degrees C |
700K hours at 25 degrees C |
|
Internal Data Integrity Checks |
End to End |
Limited, none in memory buffer |
|
Maximum Operating Temperature |
~60 degrees C |
~40 degrees C |
|
Warranty |
~5 years |
~ to 3 years |
|
Features |
Spindle Motor |
Higher RPM
Tighter run-out
Spindle anchor at both ends |
Moderate to lower RPM
Lower specification for run-out
Spindle anchored at one end |
|
Media |
Full media cert |
Lower media specification and density |
|
Head Stack Assembly |
Structural rigidity
Lower inertial design |
Lighter Weight Design
Higher inertial design |
|
Actuator Mechanics |
Larger magnets
Air turbulence controls
RV sensors and closed loop RV
suppression |
Smaller magnets
No air turbulence compensation
No RV sensors or suppression - limited to
servo wedge track alignment |
|
Electronics |
Dual processors
(dedicated servo and data path processors)
Performance optimization
Advanced Error Handling
Advanced firmware algorithms |
Single processor
No performance optimization
Standard Error Handling
Standard Firmware algorithms |
|
Customization |
FW Code |
Extensive |
Limited |
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Variable Sector Sizes |
Yes |
No |
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LEDs |
Yes |
No | |
We strongly encourage you to contact the hard drive vendor of your choice to discuss the hard drive and features best suited for your deployment application.
Check your applicable Intel® Server product THOL (Tested Hardware and Operating system List) for drive compatibility with Intel® Server Products before making a hard drive purchase. Intel® Server Product THOLs can be found at: http://www.intel.com/support/motherboards/server/.
For more information, you may refer to the link below:
http://download.intel.com/support/motherboards/server/sb/enterprise_class_versus_desktop_class_hard_drives_.pdf
Operating System:
This applies to:
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