So if you’re in the industry that requires its’ drives secure erased, or even if your a security minded person.  I came across a very interesting study.

In essence it says that because there is some brains on the actual SSD itself, there is no way to be sure you’ve erased the disk.   In a normal HDD, the erase program just writes a ton of 1’s and 0’s to the disk.  The problem is when the erasing program writes to what it think is block X, the SSD might actually write to block Y.  This is because of the way SSDs try to spread out the data so that one particular area of the memory chip isn’t over utilized.

This is quite an interesting article.

http://www.usenix.org/events/fast11/tech/full_papers/Wei.pdf