I have a gaming rig with an R7 370 Gaming Edition with 4GB of VRAM on GTA V it only says that I am using 2GB (the game auto adjusted) but I randomly started noticing that after about 1 or 2 hours of gameplay I would see small drops for a few seconds, I was fine with that until they started happening back to back. Now whenever I go to the settings it says that my video memory has exceeded its limit. But I'm only using 2GB out of 4. And when I go in the setting and change the refresh rate from 50 to 60. The games crashes.