slot to 8x

The first thing to do is to check whether you have the graphics card is installed in the first PCI-E x16 slot, because if you have two or more than one PCIs x16 slot then in most of the motherboards, the first PCIe x16 slot runs at maximum PCIe bandwidth, which is x16, while the second PCI-E x16 slot runs at x8 speed only. slot bonus to 1x