Numbers are also important - at least for marketing. In practice, it looks completely different for the most part. Memory capacities grew by leaps and bounds with the graphics cards. It started with 4 MB, and then there was 8, 16, 32, 64 and, most recently, 128 MB. In the early days, you could directly use and benefit from the increased memory. It made higher gaming resolutions possible, and FSAA required more memory as well. However, the jump from 64 MB to 128 MB was initially a questionable matter.
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