bus speed issues?

[point5]

interesting you ask this question. I just upgraded my machine from 2x7970's to 3x7970's. My motherboard supports two PCIe 16x OR one PCIe 16x and two PCIe 8x. After the upgrade, all of the graphics cards work, but two of them seem to be going at half speed netting in almost no performance gain. Perhaps I am doing something wrong though because before this experience I thought exactly what undeath said.