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Comment by vladtaltos | Hacker News Reader

idle power consumption: 4 Watts - way too much for my taste... I can understand it needing 22 Watts during high speed writes but why this much during staying idle ?

for comparison I checked my external 2TB WD Passport 0820 harddisk - it uses 2.11 Watts when streaming HD video...

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I agree, that's some high idle power consumption. If I had to hazard a guess, it's the controller aggressively maintaining the charge of the flash cells [1]. Samsung released a fix, not too long ago, for a bug with flash cells losing charge for their 840 and 840 Evo SSD line [2], so I imagine it's a delicate process to get right. Are the other NAND controllers less aggressive and/or more efficient with this process? I don't know. I assume it's the same flash cells as the SATA drives but with a PCIe-oriented controller, so I hardly expect them to lose charge any faster than the SATA counterparts.

[1] http://www.purestorage.com/resources/introduction-to-flash-m...

[2] http://www.anandtech.com/show/8617/samsung-releases-firmware...

That was due to the TLC NAND Samsung used, correct? More cost-effective but not as durable as MLC NAND (which is what most SSDs, including this new Intel drive, use).

Incidentally, while Samsung did release a firmware update for the 840 EVO to mitigate the problem, AFAIK they never fixed the original 840. (840 Pro owners need not worry, as it used MLC NAND and was not affected.)

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