Vista - Vista business x64 slow downloading!!!

Hello everyone,
just found this site, while I googled to find a solution about my internet speed...

Just built my new system with the following config:

M/B: Abit IX48 GT3
CPU: Q9550
Mem: Corsair 2 Gig - XMS3 DDR3 1333
Video: Sapphire 4670 - 512Mbs
Hard: WD Velociraptor 150 Gig
OS: Vista Business x64

Everything works nicely! I had an issue in the beginning with the drivers, but I managed to find all the latest ones (Driver Detective 6.3.4.5 was giving me 42 drivers out of date; now 0, yeah!)

I only have 1 problem... a slow internet speed! I have a Netgear DG834GT modem/router, all updated, which was giving me a speed up to 6,000 Kbs (as much as my line is) in my old XP computer... still have no problem with it when I download stuff wirelessly with my laptop...

What have I done up to now... I have unchecked the QoS (even though I read this is a myth, I just tried it)... still nothing... I did a defragmentation on my hard (which was some 20+% fragmented... still nothing...

I'm going crazy here... so I connect my old, XP, PC again, and the speed goes up to almost 6,000 Kbs...

What is going on??? any ideas?

I also changed some settings using the:

c:\netsh int tcp show global

and here are the setting I have now:

Receive-Side Scaling State : enabled
Chimney Offload State : disabled
Receive Window Auto-Tuning Level : disabled
Add-On Congestion Control Provider : ctcp
ECN Capability : enabled
RFC 1323 Timestamps : disabled

which I saw that they are the best settings...

still nothing...

What else can I do???

(I also have an Abit Airpace installed to use wireless internet with this PC, but it's not even recognized by my PC, as there are no x64 drivers for it yet... so I guess this is not a reason to believe that this is a mistake[?])

Do you have any ideas??? I'm getting upset at Vista to tell you the truth... I wonder if it was too early to change to a newer OS, but I though ok, it's been around for some time now... they already have SP1 out (which I have installed too)... they should be ok...

What the H**L is going on with Vista and my internet speed???

As for watching a video in youtube or another streaming??? Forget it... every 5 seconds it stops to "buffer" for a couple of seconds!!!

I'd appreciate your comments and knowledge please!

Thanks.
Nick

PS: when I download a torrent with many users in, speed goes up to 300... never up to 600 as with XP... when I just download a file from a site, it won't go more than 110-120... and yes, I have run 2 anti-spy wares, full scan with Mcafee, have also optimized internet speed with Tuneup utilities 2008..........

Does anybody know what I'm talking about, or I am too advanced to follow???

Nothing???