No display adapter in Device Manager

I am working on a Sony Vaio desktop with a TFT flat screen monitor and XP. The screen was only displaying 800x600 size letters. When a larger resolution was requested, the monitor issued an error message: Out of Scan range and the screen stayed black. I attached a CRT monitor and was able to see the screen. I downloaded the latest driver, and it said it installed successfully. But the Device Manager doesn't list any display adapters, and I still cannot change the resolution. It is 800x600 with 16 bit colors. The properties of the driver, (Display - Settings- Advanced - Adapter - Properties) lists VGASAVE. There is not option to make changes. There is not information on the video card; it says Unavailable.
In Device Manager, there was a yellow exclamation point next to VGA Display Controller. I deleted it, and rebooted. The found new hardware message appears, then an error message: Unable to load new hardware.
Any ideas?
Thanks

The drivers are installed (least it shows they are in device manager). this was a common issue for noobs that didn't uninstall properly. i guess i went backwards on learning cause now i am a noob again that cant seem to figure it out. i will be making a note this time. (if someone is so kind and directs me to fix).

i will try to reinstallation and such manually in safe mode again seeing if that forces the agp driver to load correctly.

1. Start by booting into save mode and checking to see if it is listed then Most update packages are full installs you do not need device manager to update the driver that was done by the software you installed.
2. Check to see if it is installed by looking into display properties
   let us know!

If you right click on your desktop>properties>settings>advanced button, do you have a tab for your video card? this should tell you if the card is the one being used. just noticed that rally already mentioned this. sorry rally.
also in device manager there is an option to show hidden devices in the "view"menu at the top. don't know why your card would be hidden, but it is worth a shot.
when you say it was slow to refresh, is this happening during gaming, or is the sluggishness happening during regular internet or office-type work. if this happens during regular use, hit Ctrl-Alt-Del, and see if something is hogging your resources. you never know. good luck.

I am having the same problem (Win XP, Gigabyte mb, Athlon 1.7 ghz system) and changing the AGP X8 video card for a 512mb ATI with install disk does nothing. Video adapter stuck on 'VGASAVE'.
regards

It would be that the device is not properly configured or may not be compatible with the system. Do work out and function for thing. It will surely let the same to work as needed. It will be better for you and you can make he things to get to a better conclusion. Look out for the conclusion.

you said that you downloaded the latest driver right ? now go again to device manager then right click the vga controller that has exclamation point then update click on update driver then browse on the latest driver that you download follow on the instruction of installing it most probably it will ask to restart it and check it now if the driver you installed able to function well ( make sure you observed the installation if you encounter any error might be the driver that you DL is faulty)... after restart check again in device manager if the conflict is still there ?

maybe you have to install the right drivers .. use driver magician3.61 to identify n update your drivers