How can i overclock my Processor

Hi guys . I have got a a problem . My processor is amd athlon 64 X2 dual core processor 4600+ 2.40 GHz .
and I have got HIS radeon HD 5770 GDDR5 and i have got 2 GB of ddr2 ram and i have got windows 8 professional built 9200 .
when i play games like Mafia 2 , Fifa 12 , Fifa 13 , call of duty black ops , NFS Shift , N.A Noire , NFS Hot pursuit , NFS The run and many other games on 800*600 and all the details are on low they work on 10-15 Frame and when i play them on 1920*1080 all maxed out the work on 10-15 frame as well .
and when i watch videos on youtube for gameplays for my Graphics card in the videos these games work on 30-45 frames with fraps .
i noted some thing :- i started the task manager and then i started one of these games and then i played for 5 minutes and then i saw the usage of my rams and the usage of my CPU . the usage of the ram were 85 % but the usage of the processor were 100 % so i think this error comes from my processor .

how can i fix this problem . and i tried to overclock my processor but i couldn't do that .

how can i overclock my CPU ?

please help me guys .

I AM SO SORRY FOR MY BAD ENGLISH IT IS NOT MY MAIN LANGUAGE   and I AM SORRY FOR THIS TALL TOPIC