The first graphics card slot of z77 is x 16. When using dual cards, the second graphics card slot is the first one, and it becomes x8+x8. Part of h77 motherboard satellites ZH77A-G43, H77, the first graphics card slot is also x 16, and the x4 of the second graphics card slot is provided by the chipset. Dual card x 16+x4. Of course, the bandwidth of some low-end graphics cards X4 will not be the bottleneck. The more advanced the graphics card, the more bandwidth it takes up.
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