[Samba] bad performance Vista <-> Samba over gbit

[Neo [GC]]

Hi,

I've a strange issue with the performance of file transfers between a 
Samba server and a Vista client.

My configuration looks like this:
fileserver: Samba 3.3 on FreeBSD 6.2 ----- gbit switch ----- 
workstation: Vista x64

When transfering files between the two PCs, I get abount 6.5 to 7 MB / 
sec. On my last Vista installation I got about 40 MB / sec. I've tried 
the following:
- raw tcp transfer rates with netio: 40MB/s with 1kb chunks up to 
100MB/s with 32kb in both directions
- upgraded Samba to the most current version of 3.3 (had 3.0 before) the 
port-system of FreeBSd will give me
- set Vista tcp autotuner to disabled, normal and experimental (slight 
performance loss with disabled, about 500kb/s less)
- set jumbo frames OFF (after that, transfer from vista to bsd with 
small chunks got VERY faster, but smb hasn't changed)
- of course disabled the multimedia class scheduler on the vista client, 
as it caps transfer at about 8MB/s when audio or video is running
- tried transfer between the vista client and a MacBook Pro connected to 
the same switch with default samba of MacOS Leopard: 40MB/s
- tried transfer between the MacBook and the fileserver (samba to 
samba): 40MB/s
- tried transfer between the MacBook and the fileserver (via AFP - apple 
filesharing protocol): slightly faster at 45 - 50MB/s

So it MUST be the combination Vista+Samba, what is VERY strange, as my 
last vista installation had normal transfer rates to the same samba server.
Of course I've searched Google (for weeks indeed), but didn't find 
anything useful besides the default hacks (MMCS, jumbo frames, aso...).

Sorry for asking a mainly vista related question in this list, but I 
thought here would be the best place to find people experiencing the 
same behaviour.


Greets and regards,
Neo / Thomas Weber