I'd love to be able to say that you and grelber are on the mark, but, sorry, nope; you're correct as respects drives in general, but not as respects my specific current circumstances.

First, and as I mentioned in my OP, close to 100% of those missing 350 MB were recognized when I initially partitioned the drive.

And second, here's a comparison of my four storage devices:

1. Internal Toshiba:                    500.11 GB        Total capacity
                                                 499.37             Capacity of 4 partitions
                                                    0.74              Overhead = 0.15%

2. External WD Scorpion Blue:     500.11 GB         Total capacity
                                                 499.77              Capacity of 2 partitions
                                                     0.34              Overhead = 0.07%

3. Sony thumb drive:        1,002,438,656 Bytes     Total capacity
                                       1,002,397,696             Capacity of 1 partition (Exact same for 2)
                                                  40,960              Overhead = 0.004%

4. Patriot Xporter XT thumb drive:  8.02 GB         Total capacity (*)
                                                     7.54              Capacity of 2 partitions (7.67 last night)
                                                     0.48              Overhead = 6.0%

(*) During the partitioning process, DU showed that 8.02 GB was available but delivered 7.67 for 1 partition, 7.54 for 2, and 7.41 for 3 (at which point I quit trying).

The Patriot's overhead % is clearly disproportionate, and it could not have supported its high price, would not have garnered its excellent reviews, if that % were default. (Edit: It would never have been marketed if its default overhead % was 6%.)

I'm afraid my expensive drive has morphed into expensive trash…not even a paperweight…too light. frown

(The drive is 4 years 3 months old, but I've got no idea what "normal" life expectancies are.)

Last edited by artie505; 11/06/13 09:51 AM.
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