i'm considering upgrading from sapphire 7750 to r7 260x

[moby90]

is this a good move?
is it worth it ? or should i go with something higher ? i'm kinda low on budget
cpu: amd phenom II x2 560 black edition (can be unlocked to 4 cores)
mobo: asus m4a88t-m/usb3
ram: 4gb
psu: gigabyte 500w
video card: sapphire radeon hd 7750 1gb gddr5

 

[arges86]

So on this page (http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107-7.html) Tom's says that the card should be at least three levels above your existing one to notice any difference.
The card your looking at upgrading to is just 3 'levels' above the 7750.
So yeah, there will be some gains but not as much as you may like.

Use the other pages on the article i linked to see what is the best card in a specific price range. I'm not sure what your overall budget is. But (to a point) more is better.

 

[clutchc]

According to Tom's Hierarchy Chart, it is recommended you move at least 3 tiers for a beneficial increase in performance. The move from HD 7750 to R7-260X would be exactly 3 tiers.
http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107-7.html

Note:
If you can get the PhIIX2 unlocked to a stable tri or quad core, you should do so. If it will OC while unlocked, all the better. If you can get it up to 3.8GHz unlocked to a quad core, you will basically have a Phenom II X4 980, which is a tier 2 CPU for gaming: http://www.tomshardware.com/reviews/gaming-cpu-review-overclock,3106-5.html
At that point, you can use almost any single GPU card you can afford w/o too much worry about bottle neck.