You're spending way too much for the performance improvement that you would see. The only thing you have there that makes a noticeable difference is the CPU. If you are going to upgrade the mobo and RAM then you should go for Intel CPU and mobo for better performance.
Something like this:PCPartPicker part list
/ Price breakdown by merchant
/ BenchmarksCPU: Intel Core i3-3225 3.3GHz Dual-Core Processor
($129.99 @ NCIX US) Motherboard: ASRock H77M Micro ATX LGA1155 Motherboard
($64.99 @ Newegg) Memory: Corsair 4GB (1 x 4GB) DDR3-1600 Memory
($17.99 @ Newegg) Total:
$212.97(Prices include shipping, taxes, and discounts when available.)