The 570 GTX is a fairly new card and should be up to handling Trainz. I see that the maximum temperature for the GPU is just 97C, so if yours spiked to 90 and died, then there might very well be a cooling issue. I'd recommend powering down your computer and pulling the card. Then carefully clean out the cooling ports and fan blades. My video card(s) all have access to the fan by lifting a sheet metal cover over it. I can't tell from the tiny photos of yours if that is true also. In any case, some long-handled cotton swabs might help.
You might also see if there are any cards next to your card. If so, then can you move them, or, failing that, add additional cooling directed solely at the GPU/card assembly? When I upgraded to my current video card, I added a fan at the back of the case that pulled in air and ran it across the opening in the card. My GPU temperatures went down by 10-15 degrees C and I've not been bothered with video problems again.
My house is heated by an oil furnace and because of this a slight oil deposit is laid down on various surfaces in my house. Because of this, I clean my computer cases about every 6 months, using a bit of alcohol on a swab to clear the oil residue from fan blades.
Bil