60c seems a little high. But, AFAIK, the HD 6450 normally runs a little hot, because its designed to run without a fan.
You should be fine as long you don't get BSOD or crashes while gaming.
60*C is pretty normal for a card with poor cooling when putting it under heavy load.
89*C is reaching the upper threshold for safe GPU temperatures.
Can you post a picture of your set up? It's important to have good airflow in your case. Cool air pulling in the front and in the side down on to the GPU and then hot air being pushed out the top/back.
Dust build up is also another major factor in cooling.