I set my cpu to full speed but it is not helping. I did not encounter any crashes just that the game is just too lag to play..... I wonder what's the problem, maybe because of too many computer players?

I have that same lag problem.  The game becomes slow but not unplayable.  The problem I do get is the when the game crashes to the desktop stating that the hardware is probably overheated, antivirus could be on, or system doesn't meet game requirements.  I'll get this probably 2 out of 10 times I play.

I found the problem, it is a bug.

You can read more from th site below

http://www.hardwareanalysis.com/ content/topic/15623/?o=0

I only get this problem while playing on one map I forget the name of the map but its only on that one map.  And about the serious error I use to get that but not anymore.  Make sure your Generals and Zero Hour are both up to the correct version 1.07 for Gen and 1.02 for ZH.  Also might try some different drivers for your 5200 and make sure to fully wipe out the drivers on your computer before upgrading as to not cause anymore problems.  When I play generals I turn all the AA off and the aniscoptric filtering to 2X and in game the only graphic eye candy I have on are the 3D shadows, texture maxed, and particles at 50% and I only lag when a nuke goes off.

hey i have the same problem with my 8200 i have a nvidia 440 go and EA said that i need to update my driver "even though I have the lastest driver" All I can say is just complain to EA about this. If lots of people complain about it maybe they will do something about it.