The new OCZ Vertex 2 with 25nm NAND flash seems to be sparking a bit of a debate , let's first read OCZ on this:
Drives are now shipping with 25nm NAND. This is the next die shrink the industry has been preparing to move to. One effect of the die shrink is the traces being closer together. Because of this the NAND is not as robust as the previous generation in regards to the voltage needed for writes and erases. This made necessary a reduction in the rated P/E cycles. The most common P/E cycle rating being 3000 now instead of the previous 5000.
To still provide a drive with a reasonable life expectation the amount of NAND set aside for over-provisioning has been increased by a few GB. So, for instance on a 120GB drive, if you see an unformatted capacity of 115GB this is perfectly normal.
Any questions concerning the move to 25NM NAND as it relates to drive size should be asked in this thread. Any new threads started related to this will be closed with a link posted to this thread. Also, please remember this is the support section of the forum. If you have a suggestion or complaint about the use of 25nm NAND use the appropriate section of the forum for those posts. Any post of a non-technical nature in this thread will be removed. Thanks.
First up this, OCZ -- if you sell a 120 GB drive, people exect to get 120GB and not 115 GB, you can dwel down into the "Windows uses Binary capacity measurements 1024MiB = 1GiB" discussion, but it remains somewhat shady advertising. When you sell a 120 GB SSD, get 115 GB and then a Windows format puts it at 107GB ... that's a lot of loss we think.
Secondly due to the 25nm NAND flash memory it seems that the drive has gotten slower with uncompressible data. More info here in the thread below. So if you are planning a Vertex 2 drive, try to get the 34nm version.
BTW we expect many SSD vendors to deal with these concerns, let's wait and see how they address this.
Oh and questions to the ODMs arises here .. if things get worse and you have to compensate for life expectancy, volume size and performance, why make the transition to 25nm NAND flash anyway ?
