I have a Mac Pro 1,1 with a flashed ATI Radeon HD 4870 XFX. Had no problems with it ever. Installed Mac OS X 10.6.3 software update and now the second monitor says No Input detected. Switched second monitor to first monitor and it worked fine, but the second DVI port no longer works. Need to get this figured ASAP as I have a lot of work to do today... very unhappy with this update. Anyone else having a similar issue or have any thoughts on what to try? I've done everything I can think of. Do I need to flash it again? Seems silly to have to flash it every time you update the OS. The video card is still recognized in System Profiler. HD 4870 with 1GB GDDDR5 VRAM.