mouse/HDD noise

[Chris Kesler <chris@pconline.com>]

My girlfriend, who I've been trying to make a Linux convert of for a
couple years now, has a question she needs answered.

She's been running RedHat Linux 5.2 and Windows 95 in a dual-boot
configuration on a Pentium system for about 2 months.  Recently she needed
to make available a serial port, so she removed the serial port adapter
from her Logitech MouseMan trackball, and plugged the trackball into the
PS/2 port on the motherboard. 

Now when she uses Windows, everything's okay.  But when she uses Linux,
whether in X or at the console with gpm, she hears a noise when she moves
the mouse.  After removing the cover from her PC and putting her ear near
its innards, she's determined that the noise is not coming from the
internal modem speaker or the PC speaker.  It seems to be coming from the
the hard drives.

Any ideas?

Thanks,
Chris