If you can save up just 20$ you could get a 2GB R7 260 which will do you better in the longrun. --- I think I'm the only person on gamefaqs with a daughterboard - ToastyOne New with a moderation history more plentiful than karma. - Fossil (Moderator)
NVIDIA has actual stable drivers and great products.
AMD offers better performance for the price, but...you get AMD quality, which in my experience and many others, SUCKS! --- "I'm glad I'm not friends with any of you in real life." -All Star : GameFAQs in a nutshell
If you're comfortable with a refurbished card then the 650ti is a solid choice.
Here is a comparison between a 450 and 650ti to give you an idea of what kind of improvements you may be looking at. http://www.anandtech.com/bench/product/609?vs=680 --- Have you accepted Raspberyl as your loli and savior?