Cheetah 15K.5 SAS Product Manual, Rev. E
ST3146855SS in 3 Gbit operation
Typical power dissipation under idle conditions in 3Gb operation is 11.8 watts (40.27 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following I/O rate curve (see Figure
8). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the corresponding +5
volt current, +12 volt current, and total watts on the vertical axis. To calculate BTUs per hour, multiply watts by
3.4123.
Figure 9. ST3146855SS (3 Gbit) DC current and power vs. input/output operations per second
CURRENT/POW ER vs QUEUE DEPTH (SAT A - 3.0 GB)
Random 128 B lock Write/R ead s
0.000
0.200
0.400
0.600
0.800
1.0 0 0
1.2 0 0
1.4 0 0
012345678910111213141516171819202122232425262728293031323334
Queue Depth
Amperes
0.00
2.00
4.00
6.00
8.00
10. 0 0
12. 0 0
14. 0 0
Power (watts)
5Volt A
12 V o l t A
Watts
14 8 16 32