What GPU do I have? Where has it gone?

I have to ask this question. Hopefully I won't be demoted for something this basic, yet for me at this point I am totally lost.
I got a nice, made to order desktop in April. Lost track of original specs, but have found all the specs now through software such as Everest, and similar.
Opened the case too. Want to sell so I can get a laptop.
Here is the problem. I am almost sure I have a ATI GPU with 512 mb. Big problem though: In the past week no software can detect it, and I didn't spot it when I opened the case. Even More Frustrating and mysterious is that my Win Perf Index dropped from an inital 5 down to 1 in the last week.
The reason stated is the graphics card.
I treat my system carefully so it is not like it literally fell out or disappeard.

ANY suggestions are most welcome.

 

Have you tried checking Device Manger in Vista?

Right Click Computer>Properties>Device Manager

Check your Display Adapter

 

GPU-Z (graphics chip info utility) http://www.majorgeeks.com/download5796.html
PCwizard (full system info utility) http://www.majorgeeks.com/PC_Wizard_d3846.html

 

I did try that but didn't show anything.

 

Thank you. I will try those tonight. If I still can't find anything would that probably mean that the GPU is either dead (very early demise) or somehow is loose?

 

Here are some screen shots from tonight. Any ideas about what is wrong?
http://i288.photobucket.com/albums/ll186/MTHall51/GPU-Z1.png

http://i288.photobucket.com/albums/ll186/MTHall51/PCWizard2.png

http://i288.photobucket.com/albums/ll186/MTHall51/PerformanceIndex.png

 

Looks like for some reason your ati drivers have been replaced by the standard windows ones. Go to ati's website and download the latest ones for your card.

 

Not sure how all that happened, but now downloaded the drivers for the GPU.
Any recommendation on a particular program that can check to see if all the drivers for each component are in place, updated?

 

A couple screen shots after determining GPU and drivers for it.

http://i288.photobucket.com/albums/ll186/MTHall51/GPUDataLatest.png

http://i288.photobucket.com/albums/ll186/MTHall51/SysSummaryusingSIW.png

http://i288.photobucket.com/albums/ll186/MTHall51/WinIndexratinglatest.png

 

Driver monitoring software exists Ive just never used any and cant think of any atm.