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Old September 7, 2009, 03:32 PM
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Chilly Chilly is offline
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Sigh... Alright, let me clear this up, the i5/i7 LGA1156 chip has x16 PCIe 2.0 lanes, now the P55 chip is connected to the CPU via a DMI link, which is the equvilent of a 4x PCIe 1.1 link.

So the "20" lane figure is CORRECT, as this is by how many lanes the CPU has access to. HOWEVER, the P55 chipset has by itself a certain amount of PCIe lanes it can give out, BUT this does not increase overall system bandwidth as it must be compressed down to fit the DMI link(4x PCIe 1.1) anyways. Until Intel releases the P55 chip, there is some conflicting information on how many PCIe lanes the PCH will actually have to give out, but I can guarantee that it will have *at least* 6x PCIe 1.1 lanes.

So just to clarify, the PCH(P55) could have 1,000,000,000,000x PCIe 2.0 to give out, but it doesn't change the fact that it still has to communicate all that via the sole DMI link which has the equivalent bandwidth of a 4x PCIe 1.1 link. Hence, the i5/i7 LGA1156 CPU's can be said to only have 20x PCIe lanes to communicate with.

Having said all that, don't worry too much, there's plenty reasons why one might want to go with X58 based system vs a P55 system, but you'll be able to plug more than just 1 graphics card and a physx card in a P55 system. There are solutions out there(such as PCIe lane splitters, ala the NF200 chip) that will allow folks to plug in everything they want into a P55 based system, bottleneck issues aside.

You'll be able to have your Dual GPU+PhysX+Audio on P55 and have it work just fine, the real question will be, will there be any bottlenecking+performance issues or not, and if so, how major/detrimental are they.

Last edited by Chilly; September 7, 2009 at 03:39 PM.
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