妄想ですが、HIPMとDIPMを両方有効にするとIntel 545sの消費電力は少ないかもしれません。

https://images.anandtech.com/graphs/graph13672/pm-active-idle.png
https://images.anandtech.com/graphs/graph13672/pm-idle.png
https://www.anandtech.com/show/13672/the-seagate-barracuda-500gb-ssd-review/9