I purchased a Belkin Firewire 800 card to be able to use firewire 800 ports on my PC (which has none). What I find strange is that writing to discs through a firewire 800 connection and the belkin card goes well the first 500mb's and then it slows down to almost no speed at all.

What causes this? I read somewhere that Vista is responsible for it and I have Vista 64. But then I read it's been fixed in the version I have.
I tried to find a solution but I cannot find anything anywhere.

And I need a solution fast...