SATA internal drives



I have a 2008 20" iMac which might need a new HD soon. According to
System Profiler, the internal SATA interface is an Intel ICH8-M
3Gigabit, supports AHCI v1.1

Are any of the current SATA HDs incompatible?
Will a SATA-II drive work in this machine, or do I have to look only at
SATA-I drives?

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Pd
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