sef123 :
Thanks...I will try to buy GTX 750...
If is too expensive for my budget what else you recommend for 100$ or little more?
GTX 750s tend to be from $120 to $150. For around that price you could get an R7 260X which is actually a bit better than the 750, and I would recommend you consider it over the 750.
But if you need it soon, your original choices of the HD7750 or R7 250 are very good value around the $100 mark.
If you do have a little extra money though, have a look at the R7 260X, it's a better bang for your buck.