Vista - Copying on network shares stutters Vista

Hello,

I'm using Windows Vista Business RTM and I have a strange problem with
Networking.

When copying a large file (let's say 100 MB) on a network share, in the
first moments, the hole pc slows down and gets stuttering (even mouse
pointer). I watched on the task manager which shows VERY high kernel times
when that happens. After about 10 seconds the stuttering is gone and the
file is copied normally.

My network card is a Marvell Yukon Ethernet Controller. I'm using Vista's
build in driver, because the driver from Marvell's website is nothing better
but it get's Vista crashing sometimes.

Do you experience the same problem as me? That would be interesting for
me...

Thank you,
Andreas Guther