Your HDD is IDE, the interface is SATA. this is the same as if you put a CDROM, which is ATA33 on an ATA133 connector. It works! Hurray! You are assuming, and lacking of information. This is dangerous! Never assume if you dont know! Start to learn, then you wont have to assume. So, for your information, SATA interface support bus speed up to 150MB/s. Anything that plug on the SATA interface and run between 0 and 150 will run at the maximum speed the HDD can get. If the HDD, in the future, go faster than 150, then it wont run faster than 150, limited by the SATA interface. IDE drive, either SATA or P-ATA run at about 60MB/s.
Diff between the 7200 and 7200.7? well, 7200.7-7200=0.7... of course, more information can be found on Seagate web site, or by using google, which I wont do for you.
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