Well I doubt your system has enough cpu power to run the best graphics card.
Need full system specs including power supply make and model, cpu make and model and monitors native resolution.
OK Here is my system Detail:-
M/B. Asus P7P55D-Deluxe
CPU .Intel core i7 860
Ram. 8 GB OCZ3X1600R2LV2G
power Supply. 700 wt OCZ pro
Monitor.AOC 2434PW Full HD 24''