The other day my CC suddenly started making a loud whining noise which sounded like a failing HDD bearing, so I powered it off and replaced the HDD. However, the noise is still there, accompanied by an odd odor. Apart from these two symptoms, the CC appears to be operating normally.
I don't believe the noise is the case fan, which means it's probably coming from some electronic component. As mentioned, everything seems to be operating normally, so I'm baffled - does anyone have any idea what this might be?
Update: upon closer inspection the noise seemed to emanate from the speaker, and sure enough when I disconnected the speaker wire it stopped. At this point I'm guessing that a capacitor or similar component on the analog board failed, hence the noise and the smell? A glance at the board does not reveal any obviously blown components.
Update II: It appears that this problem is actually a common one:
http://www.youtube.com/watch?v=c-Idzb5kL5E
Guess I'll be doing a recap!
Update 2: I replaced all the electrolytic caps on the motherboard with Nichikon tantalum caps and all is well. The system works perfectly now - it even solved the problem of the system not powering-up until it was plugged in overnight.