Advanced Format 4k Drives and Error Correction Coding (ECC)

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Do current Advanced Format 4k drives actually have better Error Correction Coding (ECC) over 512k drives? And by extension have a reliability advantage? Or do they not take advantage of this yet as the ECC is the still the same and have not been expanded?

For instance is this a valid consideration when say comparing the Western Digital Caviar Green 2tb (WD20EARS) and a Hitachi 5k2000? Or does it not matter at all at this point?

(The title and contents are formatted this way to aid in future searching, which I tried to do before hand, due to the shortness of the actual shorthand terms.)
 
i think the extra ECC is meant to enable the manufactures to create drives with a greater capacity as the drive heads can make more errors without causing a true error (the denser the platter the more accurate a head must be and he more susceptible to vibrations they are).

with current drives in theory (as mentioned above) they should be more reliable (at least from a read perspective) as it is obviously possible to create a drive using the lower level ECC. This does not however mean that the manufacture are not just using lower quality read heads and actuators to cut costs instead there by nullifying that gain.
 
Oh is that how it works? I thought it was because there is more space allotted to ECC that you can use stronger algorithms in theory for better ECC, but the change to 4k by itself if using the same algorithm nets no advantage?

The reason I am wondering whether it is being actually taken advantage of is I believe Western Digital said one of the advantages was better ECC for 4k drives (when they first launched) but also mentioned that this is not something they are considering at this time. I assume if they did improve ECC at the time compared to competitors they would strongly market it as such?
 
According to the spec sheets, the 4KB sector drives do not have any advantage in UBER (uncorrectable bit error rate) over the 512B sector drives.

I suspect that the manufacturers have not implemented significantly stronger ECC with the switch to 4KB sector drives. The most conservative approach would have been to simply mux/demux the 512B sectors to 4KB sectors, while maintaining the same ECC. I guess that they will not implement stronger ECC until even higher densities force them to it. But that is all guesswork. The only real data we have is that the spec sheets show no advantage in UBER for the 4KB sector drives.
 
Yea, I'm assuming to that they would note any advantage somewhere to help differentiate there product if it were implemented.

Went with the Hitachi 5k3000 2tb then, since it was the same price but with a $10 rebate.
 
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