SamerAyman :
since mantle is released i didn't get any increase with my rig ( 7970 dual x , i7 3770 , gigabyte p75 , 16 ram 1600 mhz ) what's is wrong ?!
mantle only works on mantle supported games..
it lowers the load on the cpu and gives it to the gpu which gives you good framerates but also gives developers a chance to make highly complex games by the ability to make higher draw calls that usual cpu load
also when you have a mantle enabled game and you have like a 6 core or 8 core cpu then it will spread the load equaly making use of all cores instead of pressuring limited cores while rest of them idle
a ton of developers are supporting mantle at this moment because directx12 will be very late untill released (late 2015 early 2016)