ESX-Error not able to reset

Hallo

On my ESX-server i had a warning on a virtual server about video memory. This warning creates an alert on applications manager which is unable to reset:

Insufficient video RAM. The maximum resolution of the virtual machine will be limited to 1672x1254. To use the configured maximum resolution of 2560x1600, increase the amount of video RAM allocated to this virtual machine by setting svga.vramSize="16384000" in the virtual machine's configuration file.

Is there a possibility to reset the alarm on my applications manager?

Other question: is it possible to monitor the whole vcenter instead of every single esx?

Thanks

phinel