54°C is  a good temperature for most hard disks. All hard disks (except the 7K60e) can handle up to 65 °C.

Even in my huge 8600c the very cool 7K60(non e) reaches 49°c when heavily used. The hard disks in my old 8100 got to 73 °c (which was way to hot!).

If you would like cooler temperatures you should download fangui and actively control your cpu temp (if possible on the 600m as it may not be supported by the program). When the CPU is cooler the interior of the laptop doesn't heat up that much and so the hdd is also cooler.

I don't know if it's worth the trouble though, as long as the temperatures stay below 60°c all is fine