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I've just built a new PC:

  • Asus P6T Deluxe v2 motherboard
  • i7 920
  • Sapphire HD 4670 Passive heatsink
  • Corsair 620hx portal supply
  • Antec P183 case

Sometimes when I turn it on, there is a high pitched "electrical" whine that comes from the PC. It doesn't happen all the time. Sometimes the PC is quiet after I've turned it on. During boot, the pitch gets higher or lower, depending upon what is currently on the screen, e.g. BIOS post screen might be higher than a black screen.

Its not the fans - I've stopped each one and the whine continues.

I don't think its the power supply - it sounds louder when I put my head near the main chamber of the case.

So I think its either the video card or the mother board, but I'm not 100%

Has anyone any idea what might be causing this, and how I can determine which component is causing it? I don't have any spare components to swap in and out to check this, and I don't want to guess at sending parts back to the supply.

Thanks in advance for any suggestions.

UPDATE: It feels like to me that this only happens when I've attempted to set up RAID1 on two of my disks. I've not been successful setting up RAID yet (that's another story), but I've disabled RAID at the moment since I'm fed up trying to get it going. The PC is not whining at the moment. My gut reaction is that this has only happened when the machine had RAID set up. I'm now going to run for a while with my non-RAID set up and see if I get the noise or not.

Thanks for all the suggestions so far.

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It is probably this problem since you said that it seemed to be related to the RAID.

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Could be your power inductors are singing or whining on a switch mode DC-DC power supply? The inductor can vibrate at different frequencies depending upon the power draw of the load (such as the CPU for the core power supply). Try putting some hot glue on the toroidal inductors on the board (especially if can hear it close up).

alt text

By the way, the sound isn't necessarily a cause for concern or indicative of a potential failure.

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can you provide a link to hot glue? do you mean from a glue gun? why does it have to be hot glue from a glue gun? I haven't tried a glue method before.. but would be very interested if it worked. – barlop May 9 '11 at 3:22

Given that you have a passive heatsink on your GPU, you wouldn't expect that to be a problem.

When I look at your motherboard it actually supposed to be quiet too. It's too bad it doesn't have integrated graphics, but you could still try to boot without your GPU (just take out the power supply) and see if you still hear that sound.

alt text

What kind of cooler do you use for your CPU and are you sure it's connected correctly?

If it's an electrical problem, if read some forum posts suggesting you should tweak your voltage settings a little bit. Given that your board is specifically made for OC-ing it shouldn't be a problem. Perhaps a little tweak will give us more information.

Plus if it's a motherboard problem, you could try a BIOS update.

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Thanks, but I don't think it's a fan. I've got 2 CPU fans and 2 case fans. I've stopped each one, but the noise continued. The video card doesn't have a separate power supply - it comes straight off the mother board. I could try booting without the video card plugged in I suppose? I've not tried that. My CPU cooler is a Noctua NH-U12p, with a push fan and a pull fan (both Noctua fans) – A_M Aug 14 '09 at 7:17
Well it never hurts to try and leaving out the GPU alltogether. Do you have the case open when you boot it, so you can try to locate where the noise comes from? – Ivo Flipse Aug 14 '09 at 7:25
The worst part is that your motherboard is supposed to have superb electrical circuits, so if it's an electrical problem that shouldn't happen... Plus you don't have a cheapo PSU, so that shouldn't be causing problems either – Ivo Flipse Aug 14 '09 at 7:34

This might actually be a noisy electrical component on a part. Either the motherboard or video card most likely. My first suspect would be the power supply, but you said that doesn't seem to be the source. Passive cooling would not stop a noisy component if that was the culprit. The frequency changes as different levels of power are passed through the component.

I know the machine will not boot, but when it starts making that whine, shut down and remove the video card, and power it back up. Leave it on for a bit, and of course it will not boot and beep at you, but you can see if it was the video card making the noise.

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Just a shot in the dark: it could be the same kind of CPU noise that occurs on (at least) ThinkPads and MacBooks using Core Duo - perhaps the i7 has similar issues. See e.g. this thinkwiki page for some BIOS and Linux settings that you could try out.

Even if you want to run Windows and not Linux, you could boot from a live Linux CD (Knoppix used to be the best-known such, but the Ubuntu install CD works too) and see if any of the tweaks fixes the whine. If so, try to find a Windows utility to do the same thing.

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Shut down, unplug something, boot. Repeat until the noise goes away. You can run a computer without a video card.

Do not unplug your CPU fan. You can apply 12v power to it by shorting ATX Pins 4 and 6 without running the system itself.

If the noise doesn't go away. stick your head in the case while it's running and listen for the direction of the sound.

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You can't run a computer without a video card, it is one of the things that is checked during POST. – MDMarra Aug 15 '09 at 3:45
BS. Tell the BIOS not to stop on errors. Either way it will let him find the source of the sound; the system will be powered. – tsilb Aug 15 '09 at 4:58
It depends, many motherboards can run without a video card just fine. Some don't though - but most if not all will at least boot and then complain and shut down again. If the sound is present immediately at power-on - this would still help troubleshoot the cause. – Oskar Duveborn Aug 15 '09 at 9:55
without the GFX card, most mobos will beep at you. However, they will still be on and running, so you can check whether you can hear the whine inbetween beeps. – gbjbaanb Aug 20 '09 at 14:14

Did you connect the 6-pin PCIe power connector to your video card? Some video cards let out a high pitched whine when that connector is unplugged.

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Hi. No, I've not connected any power supply to the video card. In fact I can't even see a power point to connect to - perhaps I'm being dim! The card is one of these: – A_M Aug 15 '09 at 12:50
Looking at your card, it doesn't seem that there is an aux power connector. I googled the 4670s and most do, but in your case it doesn't look like you have to worry about it. – MDMarra Aug 16 '09 at 21:26

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