GNOME 3 preview has problem

I have installed edu life suse 11.3 and when I logged in with GNOME 3 preview … screen blincked 3-4 time and there was no panel after that I automatically logout from gnome3 environment. How to fix it ?

Did you disable desktop effects?

Cheers Malcolm °¿° (Linux Counter #276890)
SUSE Linux Enterprise Desktop 11 (x86_64) Kernel
up 21:58, 2 users, load average: 0.06, 0.04, 0.00
GPU GeForce 8600 GTS Silent - Driver Version: 256.35

oh !! I haven’t disabled desktop effect. But I want to know why we have to disable this desktop effect ?

and ya !! thanks for reply. Thank you very much.

I find still that problem accuring again though I have disabled desktop effect of compiz and desktop. please help…