My XGA display burnt out on a 3-year-old T30, so I ordered the new part and when it arrived, I discovered I accidentally ordered the SXGA+ display instead!

I figured, no problem, just get the inverter card and go with it. So I did, and now I have a 1024x768 desktop in the top-left of the display, with identical desktops to the right and below (that extend past the screen). In Control Panel, it won't let me change the resolution to above 1024x768. Is there anything else I need to do to upgrade my system to SXGA+ that I don't know about, or am I just out of luck?
Also, I have colored vertical lines running all the way up the right part of the screen... is this likely to be anything other than a connection problem?
Thanks in advance for any help!