Both SATA and SATA2 hard drives can be used with any SATA controller. If the SATA controller can only handle 150mb/s then a SATA2 drive will function as a SATA drive. Also, any SATA cable can be used for either a SATA or SATA2 drive. Both drives and cables are fully interchangeable.
The transfer speeds of 150mb/s and 300mb/s in no way mean that a SATA2 drive is twice as fast as a SATA drive. Current hard drives are not even able to fully utilize the 150mb/s transfer speed. These numbers are more descriptive of burst speed.
300mb/s eg SATA2 is the maximum burst transfer rate, usually only hit occasionally when transferring large files from 1 SATA2 hdd to another or other large highspeed transfer situations.