See posts # 38 and 40 here:
Post #40 mentions your Dell 510m.
And the bug report on the Ubuntu wiki here:
So when you boot the Ubuntu CD (or from a usb stick), hit F6 for other options, and type in i915.modeset=1
and hit enter. You may get a message that Ubuntu is starting in low graphics mode, as it says in post #38 of that thread. This is ok though. Just proceed with the install.
If you still have the problem after Ubuntu 10.04 is installed, then try what it says in "Workaround A" on the Ubuntu wiki:
echo options i915 modeset=1 | sudo tee /etc/modprobe.d/i915-kms.conf
sudo update-initramfs -u
and reboot. Hope this works ok for you. Write back if you need more help.
And welcome to the LQ forums!