Uups, answered faster than my brain processed what I read
But Continu0 is probably correct: Windows XP's DirectX 9 is only half-heartedly supported in CloD, 2.5 GHz is at least .5 below what is needed, and a 440 with 1 GB is too weak and has too little memory, too.
Sorry, sgt_fury. Try to get used hardware with higher specs, e.g. a i5-2500 and a GTX 580 with 1.5 or 3 GB would do nicely and install a second hand Windows 7 64bit.