Slow USB flash drive on Vista

Hello group members,

After installation of some software on my fresh install of Vista x86,

I have trouble reading and writting to my USB flash drive efficiently:

it takes me 4 minutes to see the context menu pop up when I right

click a file on the flash drive, and it takes 30 seconds to response

to a delete click by firing up a question dialogue box, copying a 15Mb

file takes 10-15 minutes.

The particular USB flash drive works blazingly fast on my other XP

machine. I tried reformatting it, and it performs the same with these

issues on Vista.

Here are some other symptoms:

- The Vista machine read and write on my other USB hard drive (not

flash) without any slowing problem.

- Some time, the USB flash drive responses reasonably fast every time

when it is first plugged in during its first 20-30 seconds, and then

it becomes painfully unusably slow.

- *** I booted into SAFE MODE of Vista, and the USB flash drive reads

and writes as fast as it does on my other XP machine.

I really want to locate the origin of this particular problem. I tried

"tasklist" and "tasklist /svc" to scan processes before and after

having the USB flash drive plugged in (in Vista Normal mode), and have

discovered nothing special. Can use some other tools in sysinternals

(e.g. process monitor / process explorer) to locate the origin of

problem?

Please point me to how I can do that... Thanks!