I bought a new hard drive for my computer and installed it as a second hard drive (80GB), formatted it partitioned it etc. it worked fine for about 1 hour then the computer shut down and attempted to restart but couldn't and attempted again and again, so i shut the computer down left it for a couple hours turned it on again, it worked fine again for about 1hr 30mins then the same thing happened again, i did notice this time that for about 20 mins before it shut down every now and again there was a whining/schreeching sound. Again i left it off for about a half hour turned it on again, same thing happened again. My computer is 18 months old and the original harddrive is a 40GB one. Anyone any ideas?

Remove the new HD and try it. If it works without the new HD, take the HD back and try another one.

Check the processor fan is clear of cables - u may have inadvertantly obstructed it, cos it sounds like overheating to me !!

You have a bad hard drive, now just figure out which one. Given the tight tolerances they have to be amnufactured to, it's almost a miracle that they work at all. The screeching sound is most likely the read/write head rubbing on the spinning platter. You should take it back to where you bought it, but if they won't swap drives with you, you can just send it in to the manufacturer. They're all pretty good about replacing drives.

Hello, It could be a bad HD... however you might want to check you BIOS and see if the HD was detected. If not you will have the same problem. Hope this helps notimeoff

Since posting my original message, i took one of the side covers of, and turned the computer back on again, it has now been running for 13 hours without shutting down, but the whining noise is still happening, i can only assume that the computer was overheating and as you say one of the harddrives is faulty.