Remove the stock cooler, clean and apply new thermal paste.
Otherwise, why do you feel you need a different cooler? If it's high temps- your real issue is likely poor case airflow, not your GPU cooler. Getting a new GPU cooler still lends the GPU to still get poor temps until you fix airflow.
Remove the side of your case; blow a house or desk fan on high into the case. If your temps go down, you have an airflow problem. If your temps remain the same, you can then consider other hardware cooling options.