high screech sounds like a BIOS beep or the CPU overheating sensor!. Go into your BIOS and look for health monitor or temps and look for the CPU temps and fan speed.
I think my sensors are messed up, and have been for a while. My CPU temp is always at 80 degrees Celsius. If that were true my CPU would've burnt out a very long time ago.
well, thats maxtor for ya...possibly the hdd, but is very likely that its the overheat alarm...and wow, 80C is up there, mine runs at 20C...check in your bios for a temp readout that will tell you the temp.
also, how old is that hdd? ive done some reading, and it was designed to last for a period of five(5) years.