restart windowserver without reboot
I am working with a MacPro in HighPerformanceComputing. This means I would like to avoid a reboot. Unfortunately, after a frozen keyboard/mouse event nothing helped. We could restart the Finder over ssh, but no unfreeze happened. Unfortunately, we killed the windowserver (Quartz) process and now we have a black screen (no video displayed). Jobs are still running fine. How can I restart the windowserver under Snow Leopard just as this would happen after a restart (launch CoreGraphics) without rebooting? Any unix geek out there knowing the inside of Snow Leopard well enough? The keyboard issue I will put on a different thread after I have a video signal again. Those who cannot imagine why one would not press the power button: Some use Macs for doing big calculations and those are running for months and since they are iterative, one would lose months of work in some cases at shutdown.
Mac Pro, Mac OS X (10.6.8)