I'm planning an upgrade to a P55 platform and have a few questions. I've searched pretty extensively and have seen conflicting statements on this so I'm just as confused as before...
First - I have noticed that some mobos, such as the P7P55D Deluxe, are listed as supporting auto switching between x16/x1 and x8/x8 operation for the two primary (CPU-related) PCI-E x16 slots. In the former scenario, will the second slot actually operate in x1 mode if I put, say, a x1 sound card in it? Or will ANY card in the second slot drop things down to x8/x8? If the latter, even if it's just semantics, why isn't it referred to as x16 with the second slot disabled?
Second - I understand that given the limitations of P55, the PCH provides 8 PCI-E 2.5GT/s lanes and that some of these are used for onboard devices. The third PCI-E x16 slot typically runs at a x4 electrical link, which is provided by the PCH. My question here is, if I were to populate the first two PCI-E x16 slots with graphics cards, and populate the third (x4) slot with a card for PHYSx, what would typically happen to any remaining x1 slots on the mobo (I expect some variance between different models and manufacturers)? Since the remaining number of P55-provided lanes would be 4, I would imagine that the SATA and an ethernet controller would take 2, leaving up to 2, so in theory it should be possible to use a x1 sound card in one of the x1 slots, provided I'm not using an additional SATA controller or second ethernet controller. Am I correct in this?
Hopefully some of you can speak from experience as I'd prefer to fully understand what I'm getting into before actually buying parts and hoping works like I expect...
Thanks!
First - I have noticed that some mobos, such as the P7P55D Deluxe, are listed as supporting auto switching between x16/x1 and x8/x8 operation for the two primary (CPU-related) PCI-E x16 slots. In the former scenario, will the second slot actually operate in x1 mode if I put, say, a x1 sound card in it? Or will ANY card in the second slot drop things down to x8/x8? If the latter, even if it's just semantics, why isn't it referred to as x16 with the second slot disabled?
Second - I understand that given the limitations of P55, the PCH provides 8 PCI-E 2.5GT/s lanes and that some of these are used for onboard devices. The third PCI-E x16 slot typically runs at a x4 electrical link, which is provided by the PCH. My question here is, if I were to populate the first two PCI-E x16 slots with graphics cards, and populate the third (x4) slot with a card for PHYSx, what would typically happen to any remaining x1 slots on the mobo (I expect some variance between different models and manufacturers)? Since the remaining number of P55-provided lanes would be 4, I would imagine that the SATA and an ethernet controller would take 2, leaving up to 2, so in theory it should be possible to use a x1 sound card in one of the x1 slots, provided I'm not using an additional SATA controller or second ethernet controller. Am I correct in this?
Hopefully some of you can speak from experience as I'd prefer to fully understand what I'm getting into before actually buying parts and hoping works like I expect...
Thanks!