I'm baffled by my video card

[bosamar]

I purchased a new 128MB video card for my PC because the intro video (flying thru space...the moon.....the earth....focus on middle eastern castle and war...etc) ran very choppy. In addition I could only run CIV4 in low graphics mode. After I installed the new card the video played great and I was able to run graphics in high.

Now fast-forward 3 weeks later....I tried to play the intro again and it's back to the old choppy version. What went wrong?

Here are the specs of my PC:

Win XP Home with SP2 and all updates
MSI KT4V main board
CPU AMD XP 2100+ CPU @ 1.73 GHz (Palamino 0.18) Socket 462
DDR DIMM Slot 1 256MB Kingston PC2100 CL2.5 DDR RAM
DDR DIMM Slot 2 256MB Kingston PC2100 CL2.5 DDR RAM
DDR DIMM Slot 3 512MB Kingston PC2700 CL2.5 DDR RAM
IDE-1 Master Western Digital 40GB 8MB cache 7200 RPM HDD (NTFS)
IDE-1 Slave Sony 16x DVD (DDU 1621)
IDE-2 Master LITEON 52x32x52 CD-RW
IDE-2 Slave Western Digital 120GB 7200 RPM HDD (NTFS)
AGP MSI FX5200 8X128MB DDR
PCI-1 Open
PCI-2 SuperaMax 56i modem
PCI-3 Open
PCI-4 Sil 3112A SATALink PCI Host Controller
Slot 1: Seagate Barracuda SATA 120GB 7200 RPM HDD (FAT32)
Slot 2: Open
PCI-5 Open
PCI-6 Open
CNR Open

Please help and thanks in advance....

 

[bosamar]

I discovered the problem. When my screen is set at 1152x864 it runs fine. When I set it for 1280x720 it gets choppy....