I used the 5820k OC'd to 4.5 since I bought it 3 years ago (that's probably why it died too) and it worked like a charm. It was very rarely slow when using tons of demanding apps (like photoshop, after effects, vegas etc.) and streaming. I do intend to overclock just a bit, maybe 10%. Current cooler is NZXT Kraken X62. And for your last question, I am from Romania .