thats vram missing from your graphics and common when a fresh patch or settings are too high... on laptops it can also happen after a while because of heat build up
i would assume save/ reload should fix it unless your system is also doing something else in the background... another thing to try is disable the cross-save option as that may be having trouble finding a network to their server + you only need to synz game saves after you finish playing for the day not during actual play
