I don't know if there are any widgets that monitor your GPU temps. I know they have them for CPU. But the closest thing that I have going is MSI Afterburner. When I boot up, it is in the task bar.
So I click on it and pop's right up and I can view it at any time. Also when I game it is on the screen at the same time as I am playing. Also I can use it to OC. I can use it to monitor fps and GPU usage.
I can set way points for my fan to increae when my temps increase. All that on the screen while playing in realtime. You just have to figure where on the screen you want to put it. I will link it to you along with the manual. Good luck I hope this helps.http://event.msi.com/vga/afterburner/download.htmhttp://event.msi.com/vga/afterburner/images/Afterburner%20User%20Manual.pdf