Well, lately, I have been having problems with my WD 120 GB HDD. It has always been in UDMA 5 mode, and I have never had any problems with it, but now the drive is only on PIO mode, and I can't change it. I have checked the bios and it says that it is capable of UDMA 5, but on the device manager it is only on PIO mode, even though I have it set for DMA if available. My HDD is pretty fragmented, but it has always been that fragmented, and I've even had it much more fragmented before, and it has always worked fine for me. My drive also makes a wierd high pitch noise everytime it's reading and writing. I can't burn my stuff on DVD, since it always messes up; my HDD can't keep up. I was thinking of reformatting it, but I can't back up my stuff; I can't burn. Do you people think that my HDD is pretty much worn out? Should I buy a new one? I always leave my computer on. Maybe it got worned down from that?