It sounds like your system is having some problems you may need to take it to the store to get taken care of.
Since you have tried changing hard drives and the same thing seems to occur, if you were not in any type of warranty and wanted to work on it yourself, there are only a few things I could think of.
First, does it appear to run hot? Does the cooling fan stay at high speeds all the time or change speeds often?
Can you check the bios to see what type of SATA controller is being used, AHCI or IDE, or RAID?
Have you tried updating the SATA controller drivers? I notice it has an AMD chipset, have you tried updating the drivers for that?
Have you tried running a memory test on the unit?
Do you have access to install media other than the factory version? Do you have an old hard drive you could swap out and try running Ubuntu or some other OS? I don't think it is the actual OS, but maybe something the factory has added, or some drivers included for certain devices..
Again, if there is any warranty, it would seem to be a good time to use it.