f10beta frozen screen of death

[Bruno Wolff III]

On Wed, Oct 15, 2008 at 18:40:15 -0700,
  Jim Hayward <jimhayward at embarqmail.com> wrote:
> 
> I can add a "me too" for this problem. F9 was rock solid stable. A clean
> install of F10beta will lock up randomly. Sometimes within minutes of
> logging in. Using Firefox seems to make the lockups occur more
> frequent. 

You might try booting with nomodeset. I have a r530 based card and while things
are getting better I can still coerce an X lockup or kernel crash (it's hard
to tell which is happening from the console sometimes). Things are stable
there (but at home with an r280 card nomodeset breaks things) when I use
nomodeset.
I have a ticket open for my lockups that I have been updating as I reproduce
the problem with later versions of things that are X related (kernel,
xorg ati driver, xorg server, mesa).