i recently registered here! when i click on "new posts" it always show me 2400+ results.. how can i get only new results since last couple of days?
This shows you all the new posts you have not read, by default the newest posts are first, so simply looks through the first pages to see the last few days.
It will only show posts that are actually new (which is what the link is supposed to give you). As others mentioned, you can either ignore the ones on the bottom (the newest are at the top), visit more often or you could also just hit the "Mark Forum Read" link to mark everything read as of now. Another option would be to use the "Today's Posts" link, which will just give you stuff in the last 24 hours.