Halo will not run : (

Hey guys I reformated my HD about three weeks ago, well that went well and I've been putting my games back on it for about that time. well I installed halo combat evolved and went to play the game and it sort of freezs for a second and then a little window pops up and it says:

Halo - Fatal Error
Problem: A problem occured initializing Direct3D. Hardware acceleration maybe disabled, please run DXDIAG.

Machine Info : 2200MHz, 1024MB, 320M ATI (0x4153)

[Continue Anyway] [Continue in 'Safe Mode']  [        Exit        ]
can't use ^          can't use ^                can use ^

It does this every time I try to play the game, I've uninstalled it and renstalled it and its the same thing, I went to Start menu> Run> DXDIAG
and all the DirectX stuff was fine (I have directX 9.c) I even did the directX test's an such. but to no avail. So I've come to here to ask for help.

Come on, someone reply Please

I'm hardly knowledgable in the area of Halo (and/or DirectX) errors, but on the offchance this works: CD-installed Unreal Tournament GOTY kept crashing on me, so I uninstalled that and then decompressed a ZIP of essential files that a friend had sent me and that worked perfectly. As far as I can tell, the two copies are identical.. except that one was installed and the other wasn't.

So, try copying the files off the disc/s instead of running the installer? (Or get someone to send you the files if you can't copy them right off the disc.)

>>1
could be a video driver problem.
Try www.omegadrivers.net and download one of those. Uninstall your current ones then install one of theirs.

The DNA drivers are pretty good too.

Try and install an older version of a video driver, instead of the latest one.

>>4
I have the omega drivers for my video card, FYI my video card is a Radeon 9550 OC'ed from 250mhz core to 408mhz core. it had a passive heat sink on it so i put a fan heat sink on it. it runs cooler now than before. it can now run half life 2 on high settings. I just cant figure out what the problem is.  

>>6 I dont know where to get the older drivers.

help! i really need help! i have the same error as the first one here rited. can someone please help??!