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Looks to me like the 400GB costs less.

DiskDiff.png
 
Yeah that doesn't make much sense, but sometimes you just need to take advantage of a good deal when you see it!
 
Looks like the 500GB model is for whatever reason "obsolete" - it doesn't show up on seagate's webpage of model listings.

perhaps it was replaced by the 750GB?
 
faster rpms, some hd have like built in proprietary technology, could be the reason
 
faster rpms, some hd have like built in proprietary technology, could be the reason

AFIK, Seagate only makes Barracuda, and SV35 series drives at 7200 RPM, and only in SATA, or IDE configuration in those sizes. Size for size, I also believe that the transfer speed, and seek time is identical between the 400 and 500gb drives.

It is quite possible that the 400gb version is actually a SATA drive, but I would doubt it
 
Looks like the 500GB model is for whatever reason "obsolete" - it doesn't show up on seagate's webpage of model listings.

perhaps it was replaced by the 750GB?

It is listed on this page...curiously, it's the first model listed with a capacity of "N/A". Clicking on the model number takes you to its product page.

For whatever reason, Amazon's got it on what looks to be a closeout-like deal.

But yes, I'd probably opt for popping a Seagate Barracuda into a separate enclosure in order to get the benefit of the full Barracuda warranty.
 
well i got an email from amazon today saying that they regret they are unable to fulfill the order and refunded my card. and now the price on amazon is $279 - $60 higher than what I originally ordered it for.
 
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