mid-game screen blackout on PC

[Dooku's Brother]

Just got a new computer and didn't realize how beautiful this game really is. My increased processing speed has added new depth to this game. But it's also causing me a problem I never experienced with my 5-year old computer.

 

Mid-game, doesn't matter the map, the screen will go black. Mostly black. The game map at bottm left remains and remains active. If I move the mouse, the map will rotate. I can also hear everything that's going on and if I click the mouse it sounds like I'm shooting. But I can't see anything.

 

What can I do?

 

 

My new computer:

 

[Processor] AMD Athlon64 X2 3800+(Dual Core/2.0GHz/L2=512KB x2/939pin)

[Memory] SAMSUNG DDR SDRAM PC3200 1GB (512MB x2)

[Hard drive] (200GB) Seagate ST3200822AS

[Hard drive (additional)] (200GB) Seagate ST3200822AS

[Motherboard] (nForce4 SLI) ASUS A8N-SLI Deluxe

[Video card] nVIDIA Geforce 6600GT 128MB (PCI-E/DVI/TV-OUT)

[sound card] CREATIVE SB Audigy2 Value Edition (OEM)

[Ethernet] 10Base-T/100Base-TX LAN Broadband Port

[Operating System] MS Windows XP Home Edition ENGLISH OEM