Hi everyone,
My HDD is a Maxtor D740X-6L, I got it from a friend since my old one stopped working.
I have a software called SpeedFan and it measures the temp. of the CPU and the HDD. It shows always that the HDD is getting hotter and hotter. Now the temperature is 47*C but after some hours it becomes even 50-55*C
what might be the problem of the rising HDD temperature?

Not really sure but have seen up to 55 is max temp you would like a hd to be at (through searches and not personal knowledge)

Check this tool out to see if you can get some further info on the drive
http://www.hddlife.com/HDDlifePro.exe