How will affect the bottleneck on my system?

[Darthiss]

Hello all of you. I´ m Darthiss and I´m from Argentina.

 

I need to buy a new gpu for my computer. But the thing is that I have a shitty PSU and I´m not sure that can power enough for a 270-270x for example, that is in my budget. So I think will be better to buy a new GTX gpu that has less power consumption. I have enough money for a Zotac Gtx 960 ZT-90301-10M.But my query is: How the bottleneck with the rest of my configuration will affect the games performance. Will i have drops? Or just the amount of fps of a 270-270x.I mean, I know the performance of the gtx 960 will not be the 100%, but I want to know how it would work.

Will it work a bit better than a 750ti, the same, or worst? 

 

Because if it will work at a less efficiency and power, but will work constantly i don't have any problem. If there is going to  be drops of fps, and bad performance, not in the idea of not be able to use the 100% of the gpu, i won't buy it.

 

THANKS a lot. And I´ll leave you with the specs of my sistem.

 

-Mother: Gigabyte GA-880gm-Usb3l 

-CPU: AMD FX 4100 Overclocked to 4400mhz

-Cooler: Cooler Master Hyper 212+ 

-I used to have a xfx hd6770 but it died last january by a tunderbolt.

-Memory: 2x4gb 1600Mhz ddr3 Hiper x 

-PW: Cooler Master Extreme Power Plus 550w 

[niofalpha]

There would be a decently large bottleneck their. Nothing beyond 10 FPS in non- CPU bound games.