Wierd cookie issue

I bought a new video card (ati 850 xt pe). I am not getting the upgrade I expected from it. In the fear demo I am getting this wied stuttering problem, so I have been in contact in with ati to try and figure out why my performance isn’t as good as either I, or ati for that matter, would expect. In the process I flashed my bios and 4-1 drivers. After that I lost all of my saved information for web log ins, like my login for this site. I put my privacy settings on low, and added this site to my approved cookie list. That was the only way I could get it to remember who I was between logins. However, now it doesn’t remember the threads I have looked at. In fact, I couldn’t even see new threads till I deleted all my cookies and looked at the site not logged in. Any ideas, this is one of the only sites I look at at, would be nice to know what’s wrong.