Read this, it would explain a lot.Sir_Sandalot wrote:
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To quote:
There’s trouble a-swirling in graphics land. To make a long story short, Nvidia was recently forced to admit that the way the GeForce GTX 970 handles its 4GB memory allocation is… unorthodox, to say the least. The GPU actually taps into two separate memory pools: A primary, full-speed segment of 3.5GB, and a secondary, far slower 512MB segment. In cases where games need more than 3.5GB of RAM, some users saw stuttering and frame rate wonkiness as the GPU accessed the 512MB segment.