>Is this normal??
Looking at your specs it doesn't seem as if your computer should be old enough that you'd have to worry about fan failure or somesuch. Generally just prior to their dying a fan will make quite a bit of noise, the same is true of hard drives. However, it's most likely that your problems are either related to something that's poorly secured to your box's chassis or is naturally loud.
You can look for poorly secured objects in your computer by opening the case and looking to see if anything is moving about and/or rattling. If so, look to see if its support screws are in any way loose.
>HD
Hard drives that were created before the move to 7,200 spindle speeds generally are louder than newer ones. If you'd rather not consider getting another drive, you might want to see if your HD supports spin down, though that'd have a minimal effect if you're downloading overnight.
>CD
Variable speed drives (which constitutes most drives out there today) tend to sound like jets taking off. While this is rather annoying, it is, however, normal. The best way to stop a CD-Rom drive from making noise is to simply remove the CD that's in it
Some cheaper (and even some fairly expensive) fans can produce quite a bit of noise even while operating normally. The box fan that originally came with my case was terribly loud, even with nothing more than the fan and power supply in the case. I replaced it with a smaller, generic case fan and placed a Golden Orb* cooler/heat sink combo on my proc and have been very happy with it. Note too that if the internal temperature of your computer's case is higher, the fans will have to work harder, and thusly produce more noise. The solution then would be to try and cool your computer through some other means, usually accomplished through better ventilation.
If all else fails, you could probably set up some sound buffering material around your computer. A store that sells alot of audio-related products may be able to provide you with some.
I have no idea if either of my suggestions are helpful, good luck.
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http://www.asis-computing.com/Produc...altake_orb.htm