[pkaye]

Speed of SSDs depend largely on number of NAND die and NAND technology. As they shrink the transistor size, they leak and interact more so it becomes a little less reliable (unless improve the error correction to compensate.) Smaller size means capacity per die increases so fewer NAND die to get target capacity. The main way to get performance on SSDs is to run the NAND die in parallel. With fewer dies, the performance drops. So you can increase the number of die and thus keep performance the same while increasing the capacity. But the likely went to first route to save money.

[olliej]

Oh yeah, like I said any changes in operational characteristics are incidental to the most important bit: reduction in cost.