recently i bought zotac gtx 760 stock one, so whenever i play heavy graphics intensive games
like ac blak flag , farcry 3, my gpu goes till 83c on load, and i dont know the reason why . In
idle it stays around 33c , but in load it goes to 83c so is there nay way to solve this problem or
this is just normal ?
83c is ok, but it's not really normal, it could be due to case air flow, if you don't have proper airflow your components might be warmer and maybe even exceed normal temps. As long as you stay under 90c though you should be fine. I would add more fans to your case though. It will greatly increase performance and temps. Hope this helps!
When your GPU is hot it doesn't perform well, 83c is pretty hot, getting towards the point where you shouldn't be running the card. Once you get to 90c the card will just not work as well and it's very dangerous. The problem of low FPS probably lies in the heat of the card. If you still have a warranty for the card, I would take it back and get a new one, if you have the same problem with the new card, it's another component.
83c is pretty hot, but in those games it's all right to have it that hot, it's just not recommended, maybe think about getting more case fans. That's the only thing that will really change the temps of your GPU, unless you want to go with water and get the Kraken G10 or a custom loop, but that is quite a bit of money to spend on a graphics card.