Can i get best out of this card?(fx 6100 and hd radeon 7850)

Yes, you will be fine.

Yes and no.

Can you harness the true power of this card? Probably not. The "true power" of the card would be the absolute maximum at which it can operate with smooth FPS, etc. So let's just say the "true power" is 2 xx inch screens at XXXX by XXXX resolution with XX AA/AF and so on.

Is there anything in your setup that looks like it might be a major bottleneck for your card? No. Your card should perform to the maximum that it can with your current setup. It seems to be fairly evenly balanced and I wouldn't think there's any real issues.

Your resolution does partly depend on monitor size and the resolutions allowed by it. Some monitors may cap at 1920x1200, some may go higher, some may go lower. A Higher resolution will not increase your FPS. If anything, it will probably decrease it. As your resolution increases, so do the area and the details that the graphics card needs to process.

Any performance tool is most likely going to recommend an upgrade unless you're running the absolute maximum in hardware, ie the best CPU, GPU, mobo, etc. So don't sweat that.

To check FPS for any game, use the program FRAPS.

As for your CPU/GPU combo, you should be fine.

no, the fx6100 is a poor gaming cpu.
http://www.xbitlabs.com/articles/cpu/display/amd-fx-812...
< look here for example its ok for some games but others it really struggles with.
http://www.tomshardware.com/reviews/fx-overclock-crossf...
It really needs to be overclocked to get reasonable performance from it. But again, that depends on the game.

sadness went wrong with my cpu !! first i was with intel ,jumped to amd in the last moment on friends advice!! even this card is a crap? is should have taken nvidia?

the 7850 is fine.