Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cwjcc!neoucom!wtm From: wtm@neoucom.UUCP (Bill Mayhew) Newsgroups: comp.sys.ibm.pc Subject: Re: High pitched whine in DEL System 200 Summary: My IBM model 80 does that Message-ID: <1700@neoucom.UUCP> Date: 11 Aug 89 14:34:46 GMT References: <6958@cloud9.Stratus.COM> Organization: Northeastern Ohio Universities College of Medicine Lines: 21 I have an old 16 MHZ version model 80. When the model 80 is sitting in the msdos idle task, the 386 chip itself emits about a 12 KHz squeal. The noise got worse when I installed an 80387 coprocessor. About a year ago, there was an article in Infoworld about 80386s emitting various squeals. I took the cover off the machine and listened carefully, and it was quite obvious that the sound was coming from the CPU chip and not the power supply or the surrounding circuitry. Depending on what's going on, the 386 emits various obnoxious chirps or buzzes while executing application programs too. Running Xenix 2.2.2 also causes the system to emit various shrill sounds. Oh yes, I unplugged the winchester drive while conducting my listening tests, so the noise wasn't coming from there either. (A 486 system must be *very* loud. I guess they don't call it a screamer for nothing! :-) ) Bill