I just installed mine in an XP machine after formatting with a Vista machine.
I am running torrents on it now and it seems to be doing fine.
HD Tune gave a max sequential speed above 130 mb/s, and min above 60 mb/s and average above 100 mb/s and average latency of 13.3 ms. The same numbers as on the Vista machine.
Does that mean that the drive is properly aligned for the 4 K in XP and I am good to go?