Overheating cpu or integrated graphics card--which is it?

I recently installed Realtemp for my new lapop, and the numbers are a bit high whenever I'm playing games. I use:

Dell studio laptop
cpu: i3
ram: 4gb
video card: hd intel integrated graphics

For example: whenever I'm on the web, chatting, etc. the cpu temperature reads 38-48C. However, whenever I'm playing starcraft 2, it reads 50-65C. I know that the i3 cpu is more than enough for starcraft 2, but it puzzles me with these high numbers. So in my wildest conclusion, I assumed that realtemp is reading the temperature from both the cpu and the nearby integrated graphics card, as 50-65C seems in the range of most gpu temperatures. I'm not that much educated in this matter so if this conclusion seems far fetched, I hope you understand.

Well that's my guess, which I'm very skeptical that it is correct.

Anyway, should I be worrying about this?