Noisey Motherboard, Worringly Noisey Hard Drive..

Hi there, I've got a faulty Seagate Hard Drive, it's an 80GB, 7200RPM and has actually been faulty since I had it, I just didn't realise. It was very slow at file transfers but I just assumed it was the standard speed to transfer files between drives (my main one with the windows partition, and the secondary hard drive for storage)

But anyway, I've fitted a new hard drive today, another Seagate Barracuda 160GB this time, again an IDE one. It's all working fine, I've put all of my 70GB of data on there, it's quick and so far all seems in order, as far as actual functionality is concerned, however, it's making a very wierd scrunching kind of sound whilst in use. It's not that loud but it's still worrying, especially after having the previous drive being faulty from the offset. Is there anyway to check if it is indeed faulty short of sending it back? I don't really want to do this as I'd lose all of my data, that'd be a bit of a nightmare in all honesty.

But anyways, that's not my only problem. My computer in general makes a fairly hideous screeching sound, only emphasised by my recent purchase of an Antec Sonata silent case, it's intermitent which only furthers the irritation, if it was consistent it wouldn't be so bad, but becuase it's so random it makes me notice it a lot more, quite oftne I'll just be sitting here waiting for it to screech again. I'm not sure of the best way to describe it, screeching is the only word that comes close, but, I'd loosely say it sounds like electricity, if that's even possible.

I've almost eliminated it to the toroidal inductor in the respect that whenever I push on them with a pencil the noise stops. I tried placing first of all some glue onto them incase it was a wierd vibration, and also some nail varnish, neither of which made any difference what so ever. The motherboard is an Asus A7N8X-X by the way.

So yeah, my PC, with all of it's silent fans, noise proof case and nicely mounted drives is actually proving to be quite the contrary. The crunching noise of the hard drive isn't that irritating, but it is very concerning that the hard drive might fail. The screeching noise is the exact opposite, I'm not concerned at all that it'll fail becuase it's been like it for around two years now, since I originally built the computer, but the noise is extremely irritating. Any help or advice would be very much appreciated, thank you!