Graphics Card Temperature

So I try to play games like red dead redemption, Ark Ascended and the GPU load goes up to 100% and then the temperature rises up to 180 degrees fahrenheit. After about 2 minutes of playing the computer restarts itself, I'm assuming because its overheating. Does anyone know what I should do? I...

My PC is being affected by this virus and all the time Windows Defender pops up and says " Threat Detected". Should I install a new antivirus and scan the entire PC or I scan using Windows Defender. Can anyone tell me a good antivirus to use to scan my computer. Thanks in advance