My rig: Gigabyte ga965p-s3, 2 gigs Corsair x2 ddr2 675, c2d 6600, 1 7200 sata, ati x1900xt, 2 nec dvd burners, Rosewill RP500-2 ATX 2.01 500W, has been squeeling when I turn it on in the morning - same location as you describe. I have just put it together after replacing a amd x2 3800 setup...