The case has no speaker. No USB alarm either cuz I don't have one.
The reason I'm positive this is the hard drive is that The one I left in for too long ended up permanently squealing. In fact the squeal turned into a buzz as the problem continued, and still makes noise in an external USB casing, but operates fine otherwise.
Freestone, I ran these specs thru the calculator:
INTEL D865GBFL MAINBOARD
INTEL P4 3.00 GHZ CPU
1024 MB DDR 333MHZ RAM
SEAGATE ST3160812A 160 GB HDD
ATX MID TOWER 300W PS
NVIDIA GEFORCE 6600 GT VIDEO CARD
this is a comment from another forum that seems applicable.
"Since your voltage drain is right on the edge, I would suspect your power supply and the demands of your video card as the source of your problem. Frankly, 300 watts isn't much with the P4 machines and newer motherboards."