Talking about this on the Overclockers fourms, couple of guys on Hard Forum with the same problem, thought i'd post here to see if anyone has the same issue: - 1x 290x in a system that had been rock hard stable for over a year, - I moved to Windows 8.1 from 7 at the same time. Other people using Windows 7. Everything is fine, temps are fine, airflow in my case is fine, card seems happy, but every now and again i get a black screen lock-up when gaming, I've seen it in Dishonoured and Battlefield 4 three times now. Every time it was after gaming for ages and ages without a problem, and every time it was during a level transition. 2600k with a mild over-clock (which i turned off, same problem). Z68 Extreme 4 with latest BIOS (i think). Antec 1200W PSU Kingston HyperX Genesis 8GB Prime 95 torture test ran for 8 hours with no problem. Very latest AMD beta drivers. It really sounds hardwarey - but i'd welcome any thoughts. Made some voltage changes and haven't had the issue since, but this was just 30 minutes of game play. Cheers!