Crucial use a sturdy metal casing for their m4 SSD and one side we can see the SATA 3 power and data connectors along with a branding sticker. The other surface has an additional sticker which gives us product details including the model name, capacity and firmware version (0001).
Inside Crucial use a green PCB and attached to it is a Marvel 88SS9174-BLD2 controller. This is a new revision of Marvel's controller, newer even than the controller used on the Intel 510 Series. Beside it are eight Micron MLC NAND flash chips and by flipping the PCB over we find 256MB of Micron DDR3 cache along with a further eight storage chips. The 25nm NAND used by Micron are branded 29F128G08CFAAB-12 and the formatted capacity is 238GB in Windows 7.
Crucial rate their 256GB m4 Series drive at 415MB/s read with write at 260MB/s and IOPS of 40/50k. These speeds are maintained over time through support for TRIM.
The drive measures 9.5 x 69.85 x 100.5mm, weighs 75g, uses 280mW in use and 100mW idle with a MTBF statistic of 1.2million hours and Crucial back this up with a 3-Year warranty.