OK, I have 30.82 installed and checked for IRQ conflicts and found none. It's still locking up. It seems to happen when CV ack is firing. Is there a setting on the Nvidia controls to smooth that out? My framerates look decent at 45 +/-. My card is a VisionTek Xtasy 6564, AGP, 64mb DDR 400mhz, 175mhz core, GeForce 3 ti200. Shouldn't that be enough card to run AH smoothly at 1024 x 768?