On Fri, Jun 16, 2017 at 9:01 AM, <the...@sys-concept.com> wrote: > > I find it hard to believe as the computer was working for 3-months > without any problem with video card in 8-bit PCI slot. >
Something was definitely lost in translation here. I suspect you might be referring to 16x slots or 8x PCIe slots? I didn't think 8x slots were all that common, but I'm not much of a motherboard enthusiast. I tend to see more 1x and 16x in most boards I've looked at. PCIe uses a serial bus with packets, so the concept of bit width is a bit more nebulous. Each lane essentially has a one bit data bus. When multiple lanes are used they aren't transmitting parallel bits for the same word, but rather each is independently sending one byte at a time sequentially, with some kind of interleaving. I believe the physical layer uses an 8bit->10bit encoding, so you could view it as an 8-bit protocol in some sense. Above the physical layer the transmissions make up packets and those packets can have somewhat large payloads (hundreds of bytes). You could almost view PCIe the way you might look at ethernet. The main difference in slots and cards is the number of lanes supported. Each lane increases the rate at which data can be sent. Any device or slot can fall all the way back to 1x if the number of lanes doesn't match. Assuming the physical connectors allow for it you can stick a 1x card in a 16x slot, or a 16x card in a 1x slot. Any lanes that have matching connections will be used. Now, most slots tend to be closed off at the end so physically a 16x card won't fit on most 1x ports but you could stick a riser in-between as an adapter - the issue is purely mechanical and not electrical. Maybe your motherboard has a picky firmware and cares which slot the card goes in. It seems just as likely that one of your slots went bad and moving it to the other makes things better. If you did have a 16x card you would of course prefer to stick it in the 16x slot to get the best performance out of it. -- Rich
