Datasheet

IBM 128 GB and 256 GB SATA 2.5" MLC Entry SSDs 3
The endurance of 128 GB and 256 GB drives is specified based on the following access pattern: 50%
random data and 50% sequential data with block size mixes of 5% of the data as 4 KB block size, 5% of
the data as 8 KB block size, 10% of the data as 16 KB block size, 35% of the data as 64 KB block size,
and 35% of the data as 128 KB block size. The entry-level drives described here are capable of 72 TB of
lifetime writes, with the workload stated above as the worse case. For the device to last five years inside
of the 72 TB of TBW, the drive write workload must be limited to no more than 40 GB of writes per day.
For the device to last three years, the drive write workload must be limited to no more than 65 GB of
writes per day.
Technical specifications
Table 2 presents technical specifications for the 2.5-inch solid-state drives.
Table 2. Entry SSD technical specifications
Specification IBM 128GB SATA
2.5"
MLC HS Entry SSD
IBM 128GB SATA
2.5"
MLC SS Entry SSD
IBM 256GB SATA
2.5"
MLC HS Entry SSD
IBM 256GB SATA
2.5"
MLC SS Entry SSD
Part number 90Y8648 90Y8668 90Y8643 90Y8663
Interface SATA 6 Gbps SATA 6 Gbps SATA 6 Gbps SATA 6 Gbps
Hot-swap drive Yes No Yes No
Form factor 2.5" SFF 2.5" SFF 2.5" SFF 2.5" SFF
Capacity 128 GB 128 GB 256 GB 256 GB
IOPS read* 45,000 45,000 45,000 45,000
IOPS write* 35,000 35,000 50,000 50,000
Sequential read
rate**
500 MBps 500 MBps 500 MBps 500 MBps
Sequential write
rate**
175 MBps 175 MBps 260 MBps 260 MBps
Read latency 55 μs 55 μs 55 μs 55 μs
Write latency 55 μs 55 μs 55 μs 55 μs
Shock, operating 1500 G/1.0 ms 1500 G/1.0 ms 1500 G/1.0 ms 1500 G/1.0 ms
Vibration, operating 2
–
500 Hz at 3.1 G 2
–
500 Hz at 3.1 G 2
–
500 Hz at 3.1 G 2
–
500 Hz at 3.1 G
Maximum power,
reads
2.0 W 2.0 W 2.2 W 2.2 W
Maximum power,
writes
3.5 W 3.5 W 4.0 W 4.0 W
* 4 KB block transfers
** 128 KB block transfers