Comment 2 for bug 551196

xsplash is loaded after X, so any resolution problems you have with it are problems with the way your X is configured. I have an nvidia in my desktop and xsplash was just fine in Karmic.

However, we're not using xsplash in Lucid by default, so unless you've done something to explicitly configure it then I suspect what you're talking about is actually related to Plymouth. Feel free to file a bug against Plymouth, but I think there is nothing that can be done there. Since nvidia doesn't support KMS I think you're stuck using something a little more primitive until you get into X.