[Solved] SEAGATE barracuda 1.5Tb / WESTERN digital Caviar 1.5Tb

Not a 7200.11 Seagate. Get a .12 model if you really want a Seagate. The .11's had a firmware problem that occasionally turned them into bricks.

I've had a terrible problem with reliability of Seagate 7200.10 and 7200.11 drives lately. Specifically, they fail out of RAID all the time. Seagate doesn't say much of anything about this in the public literature, but after multiple RMAs, I contacted them directly and their RMA "Engineer" said that the AS drives were not designed for, and would not be reliable in "Enterprise RAID" which he defined as RAID 5 or RAID 10.
When I pointed out that the RAIDs it was failing out of were on desktops, which these days come with on-board RAID controllers almost universally, he continued to insist that what I was doing was "enterprise".
It's well documented that there are firmware issues, but the real problem is that seagate is selling a product that isn't suitable for a large, and growing, segment of the market: anyone using RAID, and not making it clear that the product won't work reliably in that configuration.
I've been a loyal Seagate customer for decades (all the way back to Shugart Technologies drives in Northstar Horizons), but I have to abandon their products at this point. The combination of disingenuous marketing with testy RMA people (it's the luck of the draw, I've had some who helped, and others who were adamant that it was my fault) means that I can't rely on the things, and I have much better uses for my time than recovering data and waiting for RMAs.