External HD very slow after reinstall of xp

I recently bought a new hd and reinstalled xp sp2. I have an external USB2 500 hd--wd My Book-- which is used as a closet, pure storage with no applications installed on it. It is mostly music,sound effects files and finished video projects.
It currently has 178 gig free.

When I used to access the drive via windows explorer with my old hd it took about 20 seconds or so to get into this one particular folder which holds the finished video files.
Now it takes 87 seconds to get into that same folder. This folder contains 209 gigs of stuff.
Something I probably tweaked a while ago let me access this folder much quicker before my reinstall.

I have enabled dma, disabled indexing and enabled write caching.
Any ideas as to how to speed up access to my files on this drive?
P4, xp sp2, two gig of ram.
thanks in advance.