If I remember correctly from an other thread you posted, your using some Sony laptop. Unfortunately, this is a bad situation for yourself because besides for RAM laptops are completely non-upgradeable due to there integrated nature. Few laptops are made for gaming, and even the ones that are will never be able to compete with their desktop counter-parts. It's ashame when someone runs into this situation as there is no hope for the computer, but at the same time I can't blame HTC because an upgrade in the graphics had to be made eventually.
The best route I could see now is to ask you if you have any other computers in the house. Even if it's kinda old I've been surprised at what can run this game in spite of the graphics update. If you do have one, a DX Diag would be a nice first start and there are plenty of threads to help you get a computer in shape for the game.