My graphics card problem can you help!!!

i have a 6800 gs but seem to keep having a problem with my fps dropping i play css(counter strike source) which has a video stress test built in which i normally get 122 fps on but my graphices card is only getting 70 fps on now but if i take the card out and put it back in it goes bak to its original 122 fps but this keeps happening anyone got any idea why? the card isnt lose in its slot or anything its in the slot firmly

 

yea there all up to date and have a 550 powersupply so should be powerful enough just cant figure out why it keeps doing it gonna get new graphics card for xmas another question i have is if i get the 7950 oc can i run it along side me 6800 gs ??