There's a lot of talks that the 25nm chips used in the OCZ Vertex has only 3000 write cycles, and the performance loss is related to it. I have done some digging. Here's what I got. Review of the OCZ Vertex 60G E: http://www.storagereview.com/ocz_vertex_2_25nm_review_oczssd22vtxe60g Notice down the page the part number for the 34nm version: Hynix H27UBG8T2ATR Now the 25nm one: Micron 29F64G08CBAAA Another site has given their own opinion for the performance change: http://translate.google.com/translate?hl=cs&sl=cs&tl=en&u=http%3A%2F%2Fpctuning.tyden.cz%2Fcomponent%2Fcontent%2Farticle%2F1-aktualni-zpravy%2F20180-ocz-25-nm-nizky-vykon-vime-co-za-tim-vezi Strange thing. From the link above, it says Intel's NAND flash program/erase cycles are 5,000 cycles, exactly the same as the 34nm counterpart, and consistent with earlier claims the lifespan of 25nm chips = 34nm chips: http://www.computerworld.com/s/article/9150050/Intel_Micron_to_announce_world_s_densest_flash_memory Now the datasheet for the Hynix 34nm claims 3,000 write-erase cycles, which is significantly lower than the 25nm IMFT chip. If you look around though, you can see different NAND flash chips from different manufacturers have different write-erase cycles, even at the same process node. Intel 25nm specifications -5,000 program-erase cycles Read Performance -Random read latency: 50uS Max -Sequential read: 20ns(Min) Write Performance -Page program: 1200uS(Typ) -Block erase: 3ms(Typ) Hynix 34nm specifications: http://www.jm-chip.com/en/down/H27UBG8T2A.pdf -3,000 program-erase cycles Read Performance -Random read: 200uS Max -Sequential read: 25ns(Min) Write Performance -Page program: 1600uS(Typ) -Block erase: 2.5ms(Typ) Not only the 25nm Intel chip has significantly better program-erase life, it has better performance specifications than the 34nm Hynix chip at nearly all matters, except Block erase. Except, OCZ Vertex 25nm isn't using Intel chips. In fact, no shipping SSDs use Intel's 25nm chips yet. Does it matter? I mean Intel and Micron uses the same fabs. Maybe it doesn't. Maybe it does and currently shipping ones and/or Micron's chips are the 3k lifecycle ones. It looks like the slow speed on the Vertex E is due to implementation. In fact, OCZ has a documentation saying the lower capacity(in this case, 60GB) has half the random write performance of the non E versions: http://www.ocztechnology.com/images/OCZ_Vertex2_2.5_AS-SSD.pdf The claimed 175MB/s read and 35MB/s write is consistent with measurements(like from CDM). The 60GB version of the E must be using 1/2 channel.