Hey everyone, I usually sit over in the MBP area, since that's my computer. However, my wife uses a 24" iMac for her photography. Specs are: 24" iMac Dual 2.8GHz Intel Extreme 4GB RAM (Corsair) 320GB HDD ATI RadeonHD2600 For quite a few months, she's started having a strange problem. The computer will start making a VERY high-pitched noise that appears to be coming from the top-back of the computer. It is not through the speakers, as muting doesn't get rid of it. It's happened when she's browsing the internet and listening to iTunes. It's happened when she's loading 20 RAW/NEF files into Photoshop. So, it's not very consistent as far as processor load. Last time it started happening. I checked her fan speeds and temps to see if anything jumped out at me, and nothing was out of the ordinary. The only thing I haven't checked is whether the HDD is writing at the time, but it's not a consistent noise like I expect a HDD would be. Here's a link to a video that I snagged with Photobooth just so I could have proof when we take it to the Apple store. You'll notice that she changes the volume while it's happening. http://www.amydalephotography.com/online_uploads/iMac.mov If ANYONE can help me with this, that would be great. Not only is it hindering her work, but I also don't want anything to happen and us not be prepared. Last thing we need is to lose that computer. Luckily we keep backups. PLEASE -- if you can help, please let me know. I've searched around, but could never find anything conclusive.