The SSD is slightly smaller in the area where storage is located, compared to the HDD version (which takes a 2.5″ Serial ATA (SATA) hard drive). As such, the space is limited and you are basically having to work with 1.8″ size devices.
tnkgrl Mobile replaced their SSD with a 1.8″ 60GB Samsung HDD. The Samsung drive has 8MB of buffer and spins at 4200rpm.
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