Originally Posted by axiumone
You're going to get a variety of answers on this topic. Most of which are just hearsay and not wholly verified or based on erroneous assumptions. From my own personal testing, there's about 10% performance deficit on x16/x8 vs x16/x16, but as you've yourself stated, that's using intels platform.
Unfortunately, there will not be a way to test what the true results are on the amd platform until we see either a chip with at least 32 pcie lanes dedicated to gpu's or a motherboard that will utilize a plx/pex chip.
Having said that, I would find it unacceptable to give up performance anywhere if I've invested in a pair of 1080 ti's or TXP's.
Yeah, I know it's a lot of conjecture, but unfortunately I'm not even sure if the different platforms are capable of handling PCIE lanes in different manners .