arcing

So after 5 years of use i started hearing some arcing noises from the back of my pc , the psu had a bad fan that i lubed twice and after the second time from time to time no (its not consistent) i hear noises similar to electrical short circuits or arcing. There is no coil whine or buzzing tho...

I built my first PC (specs below) 3 days ago, and I have noticed a strange sound that occurs after it has been powered off. I noticed it the first night I built it after I installed drivers and played a game for a few hours. That night, I powered off the PC (did not unplug anything or flip the...