I did install the new graphic card Shapphire Radeon HD5450 512MB following your advice. I do not have any problem turning on the computer using Windows XP. However, when using Obuntu Linux the monitor (Flat LCD) responds with the following message " Analog out of range 90 Khz - 60 Hz. I have that monitor set up to 60 Hz. Please advice!
I am not that familiar with all the technical terminology mentioned in that update but I am pretty sure it does apply in my case. When I opened the link I downloaded and saved the update but it not solve the problem. I am thinking now that the problem might be that when I installed the drivers fort the new graphic card I specified Windows XP as my operating system. My question now is: Do I have to install the driver a second time but under Linux?