Graphics card overheating

there might be dust in the heatsink, or the heatsink is loose and not making a proper connection to the gpu chip...
If it is loose, the thermal paste has already cured because of the heat, so you need to take it apart, remove/clean the old paste from the chip and bottom of the sink, apply some new paste and screw it back on...

ok ill try that thank you

What is the make/model of your PSU?

Which coolermaster case did you get?

I agree with kari, it's probably dust or thermal paste.Just to give us a better idea download HWMonitor and post back what your GPU temps are at load and idle.

As mentioned, download this:

http://www.cpuid.com/softwares/hwmonitor.html

You can check your card's temps with it. If it's getting up to 98 - 100 degrees C that's the issue. Blow out the cards heat sink, and if necessary, reapply thermal compound.

the model of the psu is corsair cx 600 and the coolermaster case is the haf 932 advanced

here is the picture while my pc is idling


and here is the picture when my pc i loading

^^yep it's overheating, 99c is way too hot