Product comparison · 2 internal hard drives

Seagate Constellation ST91000641SS-20PK internal hard drive vs Seagate Constellation ST9500621NS-20PK internal hard drive

Key differences

HDD capacity
- Constellation ST91000641SS-20PK internal hard drive:1 TB
- Constellation ST9500621NS-20PK internal hard drive:500 GB
Interface
- Constellation ST91000641SS-20PK internal hard drive:SAS
- Constellation ST9500621NS-20PK internal hard drive:Serial ATA III
Write seek time
- Constellation ST91000641SS-20PK internal hard drive:8.5 ms
- Constellation ST9500621NS-20PK internal hard drive:9.5 ms
Power consumption (typical)
- Constellation ST91000641SS-20PK internal hard drive:6.4 W
- Constellation ST9500621NS-20PK internal hard drive:4.51 W
Power consumption (idle)
- Constellation ST91000641SS-20PK internal hard drive:3.85 W
- Constellation ST9500621NS-20PK internal hard drive:2.67 W
Weight
- Constellation ST91000641SS-20PK internal hard drive:200 g
- Constellation ST9500621NS-20PK internal hard drive:183 g

Differences highlightedShow differences only

Comparison of ST91000641SS-20PK, ST9500621NS-20PK
25 specifications	A Seagate Constellation ST91000641SS-20PK internal hard drive Model ST91000641SS-20PK View product	B Seagate Constellation ST9500621NS-20PK internal hard drive Model ST9500621NS-20PK View product
Features3 differ
HDD capacityDiffers	1 TB	500 GB
HDD speed	7200 RPM	7200 RPM
HDD size	2.5"	2.5"
InterfaceDiffers	SAS	Serial ATA III
Type	HDD	HDD
Storage drive buffer size	64 MB	64 MB
Read seek timeKnown for one	Unknown — not stated by the source	8.5 ms
Write seek timeDiffers	8.5 ms	9.5 ms
Average latency	4.16 ms	4.16 ms
Bytes per sector	512	512
Mean time between failures (MTBF)	1400000 h	1400000 h
Power2 differ
Power consumption (typical)Differs	6.4 W	4.51 W
Power consumption (idle)Differs	3.85 W	2.67 W
Operating voltage	5 V	5 V
Operational conditionsidentical
Operating temperature (T-T)	5 - 60 °C	5 - 60 °C
Operating vibration	0.5 G	0.5 G
Non-operating vibration	3 G	3 G
Operating shock	70 G	70 G
Non-operating shock	400 G	400 G
Weight & dimensions1 differ
Width	70.1 mm	70.1 mm
Depth	100.5 mm	100.5 mm
Height	15 mm	15 mm
WeightDiffers	200 g	183 g
Packaging dataidentical
Quantity per pack	20 pc(s)	20 pc(s)
Other featuresidentical
Data transfer rate	6 Gbit/s	6 Gbit/s

A dash means the value is not stated by the source. Unknown values are never counted for or against a product, and there is no overall score.