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