Question Help with understanding PCIe slots, root port and WHEA 17 ?

mikey0727

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Apr 24, 2008
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Hello,

Server Board: ASUS Z10PE-D16 WS

Recently ran into and "fixed" and issue with my old Asus Server board ( Dual Xeon ). Issue is fixed, but Id like to understand what's actually happening --

As part of a recent upgrade, I purchased an NVMe PCIE card for my Samsung 950 pro, the reason being, the M2 on the particular board is not full function, and so the PCIe performance is less than stellar. Happy to say, with the PCIE carrier, my Samsung 950 sustained write increased by about 300%.....

However, upon checking event viewer, I stated seeing hundreds of WHEA "corrected hardware" event 17 warnings....
3pSTt5x.png


Investigating a bit, the Error is coming from Intel Pci Root Port, with an "address" of 6F02... So I pop into control panel, and to my surprise I see the following:
FbhhKet.png


There are 2 sections for "PCI Root Complex", and to my surprise, each section has a "6F02", One with a usb controller card, and one which now has my Samsung Nvme....

So I dig out the manual.... and here is what it says :
P8YdRtT.png


Slot 1 and 3, the 2 slots in question, are both colored black, and called out as one x8 Gen 3 link to CPU1 / 2 - the rest of the slots are colored in gray
Oddly enough slots 2 and 4 are similar but with an X16 PCIE link and in device manager, they dont share the address, the ONLY the 6F02 has 2 entries

So I give it a go just to see what happens, and I put my TpLink Network Card in slot 1 and 3, and Move the NVME to slot 2 ( GPU is in slot 4, has been the whole time ) below is my final configuration

3znKEML.png


Tplink / Usb card are sharing "6F02" but working fine and not throwing any errors for the moment - and WHEA stops throwing warnings.

Can anyone help me understand:

1. Is it bad that 2 cards have that "6F02" address in the device manager empty?
2. If based on the manual, 1/3 are configured the same as 2/ 4 , why do the devices in 2/4 get their own address ?

For the moment I am good, but any help understanding this is appreciated -

Thank you !