that's your CPU's STOCK heatsink topped with an older-style downpush-config fan. It looks like it's come loose! That's bad. Worse you cant simply push it back in because you'll get airbubbles trapped in the exposed grease. You must remove it, clean it, re-grease it, and re-seat it.
Don't be mislead by cool CPU temp readings, that DOES NOT mean your CPU isn't part of the problem. It could very well mean your CPU heatsink is doing an excellent job of removing the hot air... and dumping it carelessly on the RAM and Graphics Card!!!
serious builders swear by push-pull config as it moves the hot air directly where you want to move it: The main exhaust fan or blowhole fan.
Sure, the graphics card will naturally run hotter than the CPU, but when building or trouble-shooting any computer, you ALWAYS start with the CPU. It's the heart and soul of the rig. I would never suggest you *only* buy a new Graphics Card cooler.
Get both.
It'll be like a brand new computer! You'll most likely be able to turn UP your graphics settings as it was established a long time ago (Doom 3) that overheating VGA ram can effect FPS!