Anothet thing that came up today, as I took the pc apart and cleaned it inside, I noticed something strange. At one point I turn it on with just the source, motherboard and HDD. But it refuses to start.
It says:
1. Detecting IDE Drives, CMOS Checksum Error - Defaults loaded. Here I can press F1 to continue or Del to enter Bios. If I press F1 I go to:
2. A black page with a lot of white writing, and among that is IDE Channel 0 - HardDisk Smart Capability - Disabled and a few second after this
3. WINDOWS COULD NOT START BECAUSE THE FOLLOWING FILE IS MISSING OR CORRUPT: WINDOWS/SYSTEM32/CONFIG/SYSTEM

And adding the DVDRROM to other IDE port, it does the same as mentioned above at the first attempt, and then it loads windowsxp just fine.
I.m suspecting that the hard disk might be close to its end, but as well it might be something else.
I.m quite sure the point 1 and were present since I bought the pc, but I did not paid attention as it always loaded the OS.

The pc still works with the DVDRom on it, but I don.t know for how long.
I found a few posts online about third party software to backup your drivers, like DoubleDrive, EasyDrive etc, but still does not hurt to ask, how do you deal with a new hardrive, new windows xp installation, in order to make it go smooth? Or is this error caused by something else?