Vista - Limited connectivity

A while ago i had posted about a limited connectivity problem. Basically every now and then for some unknown reason the network would crash and the nics would stop responding properly. After some digging on various forums i found out that the problem was resolved when i changed duplex/ speed settings from autonegotiation to anything else. The problem by forcing the speed settings is that my internet connection is not that stable since my switch is not configurable . By running a netstat -e everything i download is a discard / error. Running 3 applications for example youtube, a download manager and poker is impossible and i can only do 1 thing at a time.


I have a 680i (abit in9 32max wifi) updated with the latest drivers (up to 1gbps)
The connection passes through an old 3com switch which supports up to 100mbps and then goes to my netgear router. I have windows vista ultimate fully updated. I also have another pc next to mine connected to the same switch with an intel x38 motherboard and it doesn't have any problem at all. I ve also noticed that a direct connection with the router eliminating the need of the switch wouldn't change the limited connectivity problem.

Since i found a work around to fix this i would like to know why it happens. I ve read many posts and till now this problem appears on the 1gbps nics.
Is it a driver problem and if so, why do i still have the problem after a format? (My pc worked for a year or so without having any problems at all).
Is there another work around (I ve read somewhere something about switching the sata drive port)?
Is it a vista problem?
A router problem?


Thanks in advance for the info