Ummm..........
While the GPU itself should be able to handle much higher temps than that, I'd not call 55C "nice and cold". You could boil water on that thing. Seriously. If 55C is what its running at idle, what's it running while Aces High is going? I'll bet you are peaking at around 10 degrees more than that during heavy use. Thats hot enough to start frying components that arent designed to take that kind of temp, like stuff on your motherboard around the video card. And if the airflow inside your case isnt the greatest, you are heating up EVERYTHING in there, including your CPU.