I have a GPU which only have 6G total memory. When training a faster R-CNN detector, although I have set the input size to 224*224*3, the miniBatchSize can only be set as 2. If I set miniBatchSize as 4 or 8 or larger, there are errors that out of memory on device and the data no longer exists on the device. Now I want to buy a new gpu which support me to train 1920*1080 picture with miniBatchSize set to be 64 or 128. But I don't know how to compute the memory and other paraneters the GPU needed. So how can I decide which GPU to choose?