Re: High pitched squeal coming from a newly built computer
 

start by unplugging the PC speaker. If that's it, then make sure all your fans are plugged in and that your HSF is properly installed on the CPU.

Re: High pitched squeal coming from a newly built computer
 

it might be the power supply. my computer had a high pitched noise coming from it, and i changed the power supply for a different reason, and it went away

Re: High pitched squeal coming from a newly built computer
 

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Damn it Sam,

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My bad.

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Other than a moving part, could it possibly be my mobo giving me some kind of warning sound? The noise is significantly loud btw. Not something I can just ignore. I'll see if it's a fan tomorrow.

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I mean, is it a BEEP? That's pretty different than a SQUEAL.

edit: By the way, you can also try unplugging a harddrive, to see if the sound goes away. Probably harder than lightly touching a fan, but if it's a squeal, it's a moving part. And, as stated above, that means either a harddrive or a fan.

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It's not a BEEP, it's a pretty loud high pitched squeal. But the pitch is constant. I don't know how else to describe it other than it's a sound I imagine a mobo could make. It's not the case fan or the heatsink fan. I didn't have time to test any others before I left for work. It'll be a bit tougher to test the power supply and vid card fans, but I'll try after work.

Re: High pitched squeal coming from a newly built computer
 

you can unplug the case and CPU fans for short periods of time. Also, when does it happen, right at power up? Before bootup?

Does it go away during a reset?

I would try unplugging the fans for a short time and see if it is ok.

Does your CD/DVD drive work? I have a hard time believing that a drive could be squealing loudly and still funcioning.

Re: High pitched squeal coming from a newly built computer
 

It's not the fans. I've tested all of them. I think it's the mobo. After hearing it a few more times, it does sound electronic. It happens right at power up.

It's not the DVD drive or the harddrive because I did a powerup with both of them unplugged and still get the sound.

Re: High pitched squeal coming from a newly built computer
 

Have you tried unplugging the PC speaker yet?

EDIT: re-read OP - the computer works ok (normal stuff on screen) - My guess this is "case open alarm", check in BIOS and switch it off.

Re: High pitched squeal coming from a newly built computer
 

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Have you tried unplugging the PC speaker yet?

EDIT: re-read OP - the computer works ok (normal stuff on screen) - My guess this is "case open alarm", check in BIOS and switch it off.

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What PC speaker? Do you mean my actual speakers? The only thing I have plugged in is a screen, keyboard and power cord.

What does the "case open alarm" signify? I found it in the mobo manual but I don't really know what it does. I haven't Do you recommend I just tolerate the sound while I try changing the bios?

Re: High pitched squeal coming from a newly built computer
 

When you connected the case wires to the bottom edge of the mainboard (Power switch, reset, HDD LED etc.) - one of those was for a PC Speaker. It will be 4 pins wide, with one red one black wire.

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I don't really know what it does.

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It screeches as load as it can when the "case is open" - it is usally off in default BIOS settings, or the connecters jumpered. but it is one thing I can think of that would casue such a noise (if it is actually quite loud).

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Do you recommend I just tolerate the sound while I try changing the bios?


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If the machine can display it's POST screen and get in to the BIOS, yeah, cross fingers for good luck and do it [img]/images/graemlins/smile.gif[/img]

EDIT: It could also be a low fan speed alarm or something - are you sure you connected the CPU fan to the correct header?

Re: High pitched squeal coming from a newly built computer
 

Ok. Disconnecting the PC speaker wire didn't work. I briefly explored the bios last night but then my friends came over and I put it off. From what I saw though, it seems to be normal. Fan seems to be running at good speed, cpu and system temp seems normal (~31C), it's detecting my RAM. So if I can get this far into the bios, it's not the CPU? Could it still be the mobo? I'm going to try changing the bios options more tonight.

Re: High pitched squeal coming from a newly built computer
 

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What PC speaker?

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There is a crappy little speaker mounted inside the case of PC's, which is pretty much a relic of the days before PC's had real audio capability. It was just intended for beeps, but some old DOS games used to actually play tunes through it, and Microsoft even had an unsupported driver for Windows 3.1 that would play real sound through it, which you could use if you didn't have a sound card. The audio quality was very poor and it would pretty much hang the system while the sound was playing, but other than that it worked, sort of. There is a connector on the MB for this speaker, and I think the BIOS uses the PC speaker for the diagnostic beeps in the POST.