Noise question about my new computer

[reallyill]

I recently assembled a new computer and though my fans really aren't making very much noise, there's a high pitched whirring noice that sounds kinda wobbley. I'm not entirely sure how to describe it, but needless to say, it's kinda annoiying. If anyone has any idea what this is or how I could fix it, I'd be greatly appreciative. Here's my setup
Tiger MPX S2466n-4m with 2 AMD Athlon MP 1800+, a Matrox Milennium G550 graphics card, Turtle Beach Santa Cruz sound card, and a Promise ATA 100 IDE controller, Lite-on LTD163 DVD-ROM and an LG 32x/10x/40x CD-RW as well as a 250MB zip drive and a floppy drive. My hard drives consist of a Western Digital 7200RPM 80GB drive and a 120 GB Western Digital drive with an 8mb buffer.
all of this is housed in a coolermaster atc-201 case with with Sanyo Denki fans on the heatsinks. I am almost entirely certain though that the noise is not coming from any of the fans though...
Could it be the hard drivers that are making the noise?
any help would be greatly appreciated
Thanks

 

[kgraeme]

It is indeed very likely that it is your hard drives. 7200rpm drives are notorious for a high-pitched whine. You have two and there might some sound oscillation happening to account for the "wobbley" effect, though I have heard it in computers with just one drive (IBM 75GXP).

 

[Naythn]

My guess would be the CD drive, if it isn't the hard drives.