Hi, Yes, you just need your video drivers reinstalled...when you format, usually these are gone with all other data on the drive. Windows CD does not contain all device drivers.
So, you need to find out what video device you have on that system....need to know whether it is AGP or not, and if it is a PCI added in card type, or an onboard chip type video adapter.
Your system paperwork might tell you, if you do not recall what it was. The Device Manager may list the device, but usually has listed Standard Graphics Adapter, until the correct drivers are installed....you can look there and see.
There is another way you may be able to find a lot about your hardware....and software....download and install the Belarc Advisor, a free tool we reccommend for system inventory...it may show your motherboard, in case it does not detect the true video device, this will help you find it. Write down what it gives you for video adapter and mainboard....and post that here.
The real easy way is to look through your CDs...isnt there one for Drivers, or Applications- probably a Dell Restoration Disk, too? Your drivers are on one of those that came with the computer. If you are unlucky enough to not have any, post back with all the info you can get on what video device you have.
you can open the pc and look inside, but please be careful, just look for model numbers and brand names on the video chip or card. You can also go to the Dell support site and download the correct driver, but the problem is you have to know what you have, unless they could tell you by looking up the serial number of the computer. You should have a service tag ID either on the back or the bottom of the computer....you go to the dell support area, and type that in, giving your present Operating System, etc and it may be able to show you the correct video device.