That is quite hot for a card of that performance level, but not necessarily surprising considering you have a passive cooler. Even the extreme low end GPUs these days really need a fan. Running your card that hot will likely shorten its lifespan. To extend the life of your card, I would suggest you look for a PCI slot cooler or fan card, and mount that on the slot directly under the 5450. You can find a number of these on newegg, tigerdirect, or any other computer hardware vendor. Hopefully that will get your temps down to more acceptable levels.