Seriously, you are already aware there are separate hardware and OS/software sections for computers as well as other things like ISP? Lots of helpful people... I think (disgraceful plug for my new thread in PC hardware section!!!)
As for Avforums sport... it can get "heated"... especially when a certain Chel$ki fan is about , but on the whole it is good fun and we all take the out of each other in good jest. They sometimes also talk about other minority sports like cricket and rugby in there too!
do you mean bulletin boards like here? or do you mean actual chat rooms, ie realtime convo?
tbh there are not so many decent chatrooms around nowadays....not for specific subjects anyhow........some general and music based ones around, usually the better ones are ichat plug-in based.....trouble is people are so wary now of going in chatrooms because of the horror stories that not many exist.....bulletin boards are safer because of the time difference between answers, its less of a conversation so grooming isnt so easy for predators (whether paedo's or conmen)
I dont use any anymore so sadly cant mention any, but if you search around sites for the subjects you might find some links to irc or ichat or similar rooms...