ok, so I am looking at buying a server motherboard that only has 2x pci-e x16 width slots, and that has 4x pci-e 8x slots, and I'm curious, on newegg you can buy pci-e 8x to 16x extenssion cables and I'm wondering just how practical these are.
IE if a video card that runs on the 16 width bus will successfully work and be fully usable on only an 8x bus/port. I'm not 100% sure if it will work or if it will not, because these cables are only really used for systems that are bitcoin mining, and I want to be able to use it either for an intel xeon phi card, or for 3 or more video cards, I know that if I use one of these types of cards for a device that either uses the 8x lane or less, ie 4x or 1x, that it SHOULD work perfectly because it was designed to use that or less number of lanes. however, I am completely unsure of whether it will work for a device that was only intended to be used on the full 16x lanes...
so thats why I decided to finally register here, to query the masses here. you guys would be more likely to know the answer to this than I would, on one hand it should work because if it did not then it would not be as prevelent in the bitcoin masses as it is, on the other hand, if your trying to run a device on something less than it was designed for, then there HAS to be something that would not work like it was designed for logically.
this is not actually a problem, so take your time to reply to this, this is for a future server build that I am planning... but I'm wracking my brain trying to decide on an answer and I simply do not have enough knowledge or expertise to make one.
the parts in question: