It's a bit hard to tell just by looking at those numbers. If those are simply idle temperatures then I would say that your GPU is indeed overheating. It could be due to several reasons:
1. Dirty Case
2. Malfunctioning GPU
3. Poor Case Design (airflow)
4. Bad heatsink contacts on your GPU
I'm guessing that a newer graphics card may help a bit if your problem is 2 or 4. I would say go ahead and try to put in a new card (make sure your PSU can handle it).
