First off I would get the X4 955 and save a few. You won't really get much more from the 965, plus you can change the multiplier easily to match the 965's speed or even more. That CPU will hit 3.4 without any voltage adjustments. My X4 940 runs @ 3.6 Ghz at stock voltage, but I have it under a TRU.
For gaming you will not be satisfied with the 5450. For about $60US, you could get a GT240 that is a competent gamer. Not sure about your area, but its about the most powerful GPU without a PCI express power connector in the states.
Otherwise I would look at the HD 5750, or perhaps the HD 5670, or 4670. But that starts moving into the 80-100US range.
At 1080p, the HD5450 will be woefully inept.