Definately. I put some 5400's in my older C600's that are only P3-800's, and with the update from the 4200's they had, they all sped up for daily use.
Mine is a P3-700 & I certainly noticed the difference when I upgraded from a IBM 4200 20g to a Seagate 5400 rpm 40g drive & of course Dell said that it couldn't & shouldn't be done but I did it anyway & that was about a year ago now.
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Wayne D. Johnson
Ashland, OH, USA 44805
<http://www.wavijo.com>
