Finally fixed my P4i45GV motherboard's VGA problem, Linux crashes before when I inserted a NVidia AGP display adapter into it, some people said we need to disable intel AGP module by recompiling kernel or "blacklist" it in hotplug. I tried blacklist some time before but failed.
Last night I read more about this issue and tried to add blacklist to module.conf, it worked! Now I am using NVidia GeForce 4MX 440, although not powerful but still can do some funny thing with it.
Another problem is that I cannot use firewire hard disk with 1394 adapter, don't know why, maybe the adapter has problem, I have removed the adapter temporarily.