Ubuntu – How much does GNOME Desktop Slow Down Ubuntu Server 9.04

In NAT mode the firewall software of the host OS is managing the communication of the virtual machines to the world. Inside the host (e.g. from your guest desktop to your guest server) the communication doesn't go through the firewall. But the communication should be blocked by the firewall of the guest OS too. I suggest to change the network interfaces to bridged mode first. It will by-pass the firewall of the host OS. If the communication is working now you should configure firewall exceptions on the firewall of your host. If still doesn't work, check the firewall config on the guest. (it is unlikely the firewall of the guest blocks the communication because it works to the guest server) And you should have other firewalls over the host so anything can block your communication.

I've found the solution after hours of research, thanks to everyone who has helped.

Thanks go to kras1001 on this Ubuntu Forums thread who suggested to manually set the onboard memory to 128mb, instead of automatic. I then got rid of the i915.modeset=0 in the GRUB config and now we're up and running!

Wooooohoooooo