"The lover knows much more about absolute good and universal beauty than any logician or theologian, unless the latter, too, be lovers in disguise." - George Santayana

"To do the useful thing, to say the courageous thing, to contemplate the beautiful thing: that is enough for one man's life.: - T.S. Eliot

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I doubt that the case itself is making the noise. Squeezing the case is probably just applying pressure to whichever of the machine's components that is making the noise, causing a temporary dampening of the noise.

Does the machine have a separate video card? These sometimes have tiny fans on them to cool the graphics chip, and the fans can get noisy over time. If you find a fan like this, see if you can get your ear right up to it to see if the noise is coming from it, or turn the machine off, locate the two little wires that run from the fan to a connector that attaches to the card, disconnect it, and turn the machine back on for a moment to see if the noise has stopped. If the fan is making the noise, try blowing the dust off of it with a can of compressed air, which you can buy at office supply and computer stores.

Hard drives can also emit high pitched noises. Again, you can turn the machine off, then pull the power cable out of the back of the hard drive (it's the one that's about an inch wide, with 4 wires (red, black, yellow), and turn the machine on. It won't boot past the BIOS stuff, but you can listen and see if the sound is absent.

You can also try turning the machine on for a moment with the CPU fan unplugged from the motherboard.

If you don't have experience working inside computers, get someone who does to help you.

The Dell website has a user forum area; you can try looking through it to see if there are any posts reporting issues similar to yours, or you could start your own thread.

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my other quick thought, having not heard the noise, is that you've got crosstalk between some of the pci/agp cards, the metal in the case, onboard sound, etc. whatever power supply dell uses might be one of the parts they used to get the price to what it was. if the psu is feeding insufficient or dirty wattage to the rest of your computer, anything can go wrong with anything on your board.

BTW: Harri gave you great advice, i couldn't have done it better, but just a reminder that you NEED to make sure you've electrostatically grounded things(the band is 2 bucks at microcenter). you could end up ruining some or all of your computer otherwise.

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It's Dimension 4550. It's a clamshell case with plastic exterior and metal interior. There is a plastic duct leading from CPU to a fan on the back of the case. It also has a separate video card, nVidia GeForce4 MX.

Thanks for your suggestions. I've opened my case several times before and have problem pin-point the exact location of the sound. But will continue to observe and hope eventually I can locate the source of the noise.

"The lover knows much more about absolute good and universal beauty than any logician or theologian, unless the latter, too, be lovers in disguise." - George Santayana

"To do the useful thing, to say the courageous thing, to contemplate the beautiful thing: that is enough for one man's life.: - T.S. Eliot

[Link]

"The lover knows much more about absolute good and universal beauty than any logician or theologian, unless the latter, too, be lovers in disguise." - George Santayana

"To do the useful thing, to say the courageous thing, to contemplate the beautiful thing: that is enough for one man's life.: - T.S. Eliot

[Link]

any computer store sells bags of rubber bumpers that you could try sticking onto the case and your drives. they're under 5 bucks and can't hurt, and might stop it if it's case jitter. if you're inspired, rip the damn exhaust out of your case, and get a decent all-copper heatsink with a quality fan. it's quieter with bigger blades and liquid bearings, much cooler and safer versus what came with your p4, and useless unless you've got one of those shuttles that 14 year olds who hate sports do.
the other good thing for reducing case noise you can get are vibration-absorbing liners that you put between the fans and psu and your case. you can get all 3 of those things for approx. 30 bucks, and if it's still the case that's making noise, call a preist

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