Vista - Windows Vista Intel VE/100 Issues?

OK I have a Dell Dimension 9100. It has dual core, 4GB RAM, and Intel VE/100
NIC.
I have loaded Vista 64 bit Ultimate, Vista Home Premium 32 Bit and currently
Vista Ultimate 32 Bit. I also installed XP SP2 (32 Bit) which worked just
fine. The reason I went thru all this torture is that under any version of
Vista the network is so ungodly slow its unuseable especially with shares and
web browsing (Firefox and IE) However playing MMORPG games is actually very
fast. All this was tested under each of the OS'es above and all of this is
reproduceable. I have installed the latest Intel Vista Driver on all the
above configurations as well. I know this isnt my internet connection being
that the other PCs on my network wired and wireless are connecting just fine.
I do not want to uninstall Vista but I am running out of options. I also ran
the Internet Connectivity Evaluator with passing results
(http://www.microsoft.com/windows/usi...d/results.mspx)

Anyone have any suggestions?
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Jason M. Cornellier - VCP, MCSE, CCNA, CCP