Closing remarks

Especially concerning the PE-cycles I have to add a comment. At AnandTech one can find Anand La Shimpi doing some maths regarding the lifespan of 25nm NAND flash memory. Let's assume taht we have a drive with 100 Gigabyte capacity and seven Gigabyte of data is being written every day. In this case it takes about 14 days until every cell has been used once. In other words after 14 days you have used one PE-cycle. Apart from SandForce there is no other controller manufacturer that offers a write amplification factor of 1. Knowing this let's assume that a drive has a write amplification factor of 20 as wells as perfect wear levelling. If we do the maths now the NAND will have a lifespan of almost six years. Furthermore a write amplification factor of 20 is unlikely high but.

Furthermore JEDEC specifications state that even when all PE-cycles have been used the NAND Flash must be able to keep its data for one more year. Because of this I don't doubt the longevity of 25nm NAND flash memory.

Regarding the PE-cycles I have another remark: you might have spotted that there is a discrepancy between the PE-cycle count of Intel and Micron NAND. For 25nm Intel flash it states 5'000 PE-cycles and for 25nm Micron flash it is 3'000. How can that be especially with the background in mind, that Intel and Micron NAND flash come out of the same factory. According to Micron the reason can be found in different testing conditions. Nevertheless Intel 25nm NAND is the same as Micron 25nm NAND. If you would label the Micron NAND with the Intel brand these chips will be sold with specs telling the customer that he got 5'000 PE-cycle NAND.

Another thing you might have spotted is, that these tables are far from completion. If you do want to help updating these tables it would be very welcom if you use our forums or the commentary system.

Page - 1 - Introduction	Page - 4 - OWC Mercury, Patriot, Plextor, Samsung, Silicon Power, Super Talent, Strontium
Page - 2 - ADATA, Corsair, Crucial	Page - 5 - Closing Remarks
Page - 3 - Future Storage, Intel, Kingston, Mach Xtreme, Mushkin, OCZ

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