If you are using the Nvidia drivers posted on the Nvidia web site then you MUST reinstall these drivers whenever you update ANY of the X-server software. If you replace the kernel you will be forced to reinstall the drivers but just replacing the X-server or the open GL code does not do this. Not reinstalling drivers when video code is replaced usually causes problems. It seems like every time RH updates any video code but does not upgrade the kernel at the same time there are complaints that Wine causes machines to crash. This is the reason.