Video in certain games still jumpy

Okay, now I’m beginning to sound like a broken record but try to imagine how I feel.
I’ve just upgraded my Video card to the x800 pro, and added 512mb ram, to get rid of games problems, and part of the problem still isn’t solved.
Processor: 2.2 ghz amd
video card: radeon x800 pro agp
1.024 gig ram
200 gig hard drive - 180 gigs free
nec optiarc dvd dl rw
winxp pro sp2
etc. etc. etc. All most recent drivers, nothing running in background- yes, yes, not even antivirus software.

Yes, AREA 51 now runs beautifully, video and gameplay, even at 1440x900, but neither Deus Ex: Invisible War nor Stolen’s videos will run- properly, that is.

Yes I’ve tried the patches, either they won’t work or they don’t help.

According to my checks, these videos are on my hard drive- therefore I’ve already watched them all via RAD Tools- and they are all fine, not corrupted, etc.

The discs are in perfect condition.

My disc drive is new. WHAT ELSE CAN I CHECK?

I’ve tried working in Catalyst with SMARTGART. BIOS doesn’t seem to have a utility for it and all the settings are defaults at what seems recommended.

ARGHHHHHHHHHHHHHHHH. MAKE IT STOP DOING THIS! PuhhhLEEEEZE!

What version of DirectX is installed on your machine?

9.0c
When both applications asked to install their own versions, I said yes, figuring they’d find the newer version and work with it.
They both said the install worked right, no error messages.
???