Comment 4 for bug 257774

The opensource nv driver doesn't work on the onboard graphics but I have just tried the same steps on a different computer with ATI Rage Mobility graphics and the behavior is exactly the same. Although it didn't freeze and seemed to be usable the gdm popup sound (not the login sound, that was my mistake in the original bug report) was repeated endlessly in the running session.

I also tried with three different users (A, B, C - logged in in this order) and it was quite interesting but unnecessarily complicated to explain and debug. The two users case is simple and reproducible easily:

1) log A in
2) switch to B
3) switch to A
4) log A out -> expected lock screen of user B session but got regular login prompt
5) log B in -> gdm popup sound is repeated, with some gfx drivers the desktop is unusably slow

There is also an interesting artefact when the user B logs out at last - the gdm prompt that appears is then asking for a password and it's not clear for which user it is. But I think this is just another sign of the problem in the step 5 when the login of B tries to reuse the existing session.

Thanks.