if Seagate lock HDD plater capacity through firmware, than it is not a cost effective way to do business:

for 500GB HDD, the most cost effective way is using two 250GB platters (as of time of writing, HDD platter main-stream technology is 500GB per platter, which is put in WD 2TB or Seagate 1.5TB HDD).

I do a quick check for Seagate 500GB drive, at least two web site indicate 500GB is a 2 platter drive, which is using 250GB platter where 750GB HDD is a 4 platter drive:
http://www.pclaptop-review.com/2006/11/16/...d-drive-review/
http://www.tomshardware.com/news/seagate-i...a-hdd,2688.html

so, to get 500GB HDD increase to 750GB, it mean seagate is installing at least 3 platter into suppose 2 platter drive, then use firm ware to show as 500GB capacity.

isn't this is a funny way to do business, Seagate just need to announce to the world that they are able to sell 750GB HDD at WD/Hitachi/Samsung 500GB HDD price and beat them to death in term of sale?

There is at least RM127 different between Seagate 750GB and 500GB selling price if I based on PC Depot price list:
http://www.pcdepot.com.my/pricelist.aspx

why seagate have to hide their more superior technology or manufacturing capability compared to competitors?