New IDE drive dramatically slow system?

[Carl Fink <carl@fink.to>]

I'm puzzled.  A few days ago I installed a new Maxtor DiamondMax Plus 40 GB
hard drive on my system, replacing a fairly old 1 gig drive.  I installed it
as slave to my existing 8 gig drive, which holds Debian.  I intended to use
it for data (video files, etc.).  I created a swap partition (128 MB) and a
20 gig ext2 partition, leaving the rest of the drive unused for later.

Since booting with this setup, my system has been dramatically *slower* than
before, particularly when reading from and/or writing to the new drive. 
Even things that I wouldn't expect to depend on drive speed, like redrawing
of graphical elements in X, are something like four times slower than
before.

Does anyone have a suggestion on why this would happen?  Or where I can find
more information?

Thanks.
--      
Carl Fink             carl@fink.to
Jabootu's Minister of Proofreading
http://www.jabootu.com