I have re-installed DirectX 9 countless times, and yet my high end games (Half-Life 2, Portal, BioShock, Mirror's Edge) start getting exceedingly choppy after a few minutes of play. I have all the right specs to play these games properly and used to be able to play them without any problem. They all start out fine and then just become unplayable after a few minutes. Because this started happening a while ago, I can't do a restore point, and because the computer is old and I've moved a couple times, I can't find the original CD's to re-install Windows. I've run "dxdiag" and it says it's working fine. I've tried the "-direct81" problem to get them to run smoother, but there's got to be a way to get DirectX 9 to work properly again, right? Thanks for all the help everyone!1 person needs an answerI do too

Never mind. I ended up just upgrading my graphics card, which I've been wanting to do anyway for other reasons. I'll never know why it happened, but at least it's not happening anymore.