You should not update from Ubuntu to Mint. There are some differences that
could cause Mint to lose its Mintiness over time and cause your system to
become unstable. Treat them like different distributions. Download the Mint
ISO and burn it to CD and start with a fresh installation. Then your system
will be Mint and not a hybrid which can make giving advice almost
impossible.

If you install Mint from a fresh installation it will set up your graphics
card and your system should work out of the box. You should only go to ATI
if it is not working properly. In Linux hardware drivers are supplied from
the repositories. In rare cases you need to go outside, but this is not the
first choice, but the last one. The graphics driver is compiled based on the
kernel and if you get it from ATI then you will need to compile it first.
Lots of things can go wrong. This is not for the faint of heart as you need
to be prepared for troubleshooting or re-installing. You should back up and
prepare for the worst, just in case.

I should know. I have done this myself at least half a dozen times this week
trying to get Nvidia proprietary drivers to work with Fedora 12 and Lucid
Lynx. Sometimes compiling the driver is not enough and you have to edit
config files and even grub manually.

I read the OP's post to say he upgraded from Mint to Ubuntu...

It does not matter in the end. Mint is NOT Ubuntu and vice versa. I do not
know how many times I have seen people post "Ubuntu" problems only to find
that they started not with Ubuntu, but with Mint or Ultimate. Treat them as
different distros and do not upgrade from one to the other. The only part
that I would change is the order of Mint and Ubuntu and in the second
paragraph start with a fresh copy of Ubuntu, instead of Mint.

As for getting drivers from ATI, that part is unchanged. The first place to
go is to System, Administration, Hardware Drivers once he gets Ubuntu
working. It will recommend and install the appropriate driver. If one is not
available then he could build one using EnvyNG in the repositories. Once it
is installed run Envy and it will download and compile a driver for him. I
have used Envy and it worked quite well. He could do it himself, but it is
easy to miss a step and wreak havoc on his system.

Thanks for keeping it straight, though. He is upgrading from Mint and not to
Mint. That's what I get from trying to post during an NFL break. :)

So this envy can use the driver from ATI so you can use the card to its
full and real extent? I tried the FGLRX drivers and they fracked my system.

EnvyNG is in the repositories but here is the author's website where he
describes it. http://albertomilone.com/nvidia_scripts1.html

I have used it and successfully compiled drivers when they weren't in
Ubuntu's own repositories. Others may have different success, but I have
read many reports of others using it with success. It is one more tool
available to users to simplify a sometimes difficult task.

I don't think that it will help me with my Lucid problem though. The alpha
uses usplash still, but they are transitioning to Plymouth and have done
something that causes my Nvidia card not work with the proprietary drivers
that I have used since Hardy. I am NOT looking forward to Lucid if it
follows in Fedora's footsteps. Getting Nvidia proprietary drivers to work in
that OS is a royal pain in the butt and a major step backwards for Nvidia
users. I hope that Canonical is aware of the problems and does not leave us
in the lurch. So far it is not good.

Lucid did the following: when it installed it messed up grub2 on another
drive and wrote it to the proper drive, but mixed the kernels up. When I
tried to boot Karmic on another drive grub did not exist. When I chose the
Karmic kernel from the list it pointed not to Karmic, but to Lucid. That
meant that I could not load Karmic without using the Live CD to fix it.
Things got worse. when I installed the proprietary Nvidia drivers (the same
ones I have always used, I could not get a GUI back. I purged xserver-xorg,
cleaned apt and re-installed xserver-xorg. It has a dpkg error that nothing
will clear. So the next step is to wait for alpha 2 and re-install. The pain
of testing alphas has never been so bad.

A word of warning: if anyone is using Lucid be careful and if you have an
Nvidia card wait awhile before using the proprietary drivers. Enough of my
complaining...

Yes, it should give you full use of the ATI card's capabilities.

I used the utility and rebooted. I thought things were working and then
my screen started to do some strange blinking and really fracked up! I
uninstalled, reconfigured my xorg file and Im back to normal.

Not saying it doesnt work, just probably doesnt work with my card.