12 Barracuda XT SATA Product Manual, Rev. D
Drive Specifications www.seagate.com
2.3 Recording and interface technology
Interface SATA SATA
Recording method Perpendicular Perpendicular
Recording density (kbits/inch max) 1941kb/in 1721kb/in
Track density (ktracks/inch avg) 277 ktracks/in 240 ktracks/in
Areal density (Gbits/inch
2
avg) 488Gb/in
2
347Gb/in
2
Spindle speed (RPM) 7200 + 0.2% 7200 + 0.2%
Internal data transfer rate
(Mb/s max)
1900Mb/s 1300Mb/s
Sustained data transfer rate
(MB/s max)
149MB/s 138MB/s
I/O data-transfer rate (MB/s max) 600MB/s 600MB/s
2.4 Physical characteristics
ST33000651AS ST32000641AS
Maximum height 26.1mm / 1.028 in 26.1mm / 1.028 in
Maximum width 101.85mm / 4.010 in 101.85mm / 4.010 in
Maximum length 146.99mm / 5.787 in 146.99mm / 5.787 in
Typical weight 700g / 1.543 lb 700g / 1.543 lb
Cache buffer 64MB (64,768kb) 64MB (64,768kb)
2.5 Start/stop times
3000GB 2000GB
Power-on to ready (s) max. 18.0 15.0
Standby to ready (s) max. 18.0 15.0
Ready to spindle stop (s) max. 20.0 20.0
2.6 Power specifications
The drive receives DC power (+5V or +12V) through a native SATA power connector. See Figure 5 on page 24.
Power consumption
Power requirements for the drives are listed in the table on page 9. Typical power measurements are based on an
average of drives tested, under nominal conditions, using 5.0V and 12.0V input voltage at 25°C ambient
temperature.
• Spinup power
Spinup power is measured from the time of power-on to the time that the drive spindle reaches operating speed.
• Seek mode
During seek mode, the read/write actuator arm moves toward a specific position on the disk surface and does
not execute a read or write operation. Servo electronics are active. Seek mode power represents the worst-
ST33000651AS ST32000641AS