What's a good porgram to check my computer's CPU? Don't want to restart computer to check BIOS or download the first link I find which usually has malware.

It's been getting hot lately, but I guess it is summer and I haven't dusted it in a while. It's fairly new, i52500k, 1gb graphics card, 8gb ram if that matters. Somewhat large case too so lots of breathing room. So does anyone know a good program to check the temperature? I'm so paranoid of anything I find online without a real person's approval first.