Bit confused on that model #. I found an ST31000322CS and an ST1000VM002 at Seagate's web site, but no ST31000VM002. The ST31000322CS is listed in post 1, so we know it works; since yours isn't working, it's probably the ST1000VM002.
Unfortunately Seagate's specs don't show the exact number of sectors like WD's specs do, so there's no way for me to tell whether the 1000VM002 has more sectors than the 31000322CS or WD 1 TB drives.
Anyway, both have reasonable power requirements, so I doubt power is the issue. The main differences are the cache and the SATA interface speed. The 31000322CS had SATA II and an 8MB cache, while the 1000VM002 has SATA III and a 64MB cache. Can't see why the cache would matter though.
(Actually Seagate's Web site is confusing: one page
lists the 1000VM002 as a SATA II drive (3 GB/s) but their .PDF data sheet
lists it as a SATA III drive (6 GB/s). I'm assuming the latter.)
Perhaps the SATA interface isn't negotiating downward to SATA II. If it's the SATA interface I don't think an external enclosure will help, since you'll still be connecting via the Pal's SATA interface (only with a longer cable).
Couldn't find anything about jumper settings for the 1000VM002, but the 31000322CS had a 4-pin jumper block. The two outer pins
could be jumpered to force the drive to SATA I mode. Perhaps the 1000VM002 has a similar jumper block to force SATA II mode?