B460 Phantom Gaming 4 PCIe Speeds

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   I have a B460 Phantom Gaming 4, which has 2 x16 PCIe slots.  The manual states that the PCIe1 operates at x16 if PCIe3 is empty, and PCIe1 operates at x16 and PCIe3 operates at x4 if both slots are used.

Is this true even if the card in PCIe1 is only an x8 card?  I was hoping PCIe1 and PCIe3 could both operate at x8 if both were only x8 cards.

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Bobat Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 24 Feb 2021 Status: Offline Points: 3	Post Options Post Reply Quote Bobat Report Post Thanks(0) Quote Reply Topic: B460 Phantom Gaming 4 PCIe Speeds Posted: 24 Feb 2021 at 4:09am
	I have a B460 Phantom Gaming 4, which has 2 x16 PCIe slots. The manual states that the PCIe1 operates at x16 if PCIe3 is empty, and PCIe1 operates at x16 and PCIe3 operates at x4 if both slots are used. Is this true even if the card in PCIe1 is only an x8 card? I was hoping PCIe1 and PCIe3 could both operate at x8 if both were only x8 cards.

Xaltar Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Joined: 16 May 2015 Location: Europe Status: Offline Points: 27473	Post Options Post Reply Quote Xaltar Report Post Thanks(1) Quote Reply Posted: 24 Feb 2021 at 4:05pm
	No, looking at the images on your product page the PCIe3 slot is only electrically wired as an x4 slot. This is common with most mid tier intel chipset boards and I believe is a stipulation from intel to ensure that only their top tier boards, that are licensed for SLI, can use x8 + x8 configs. There have been some boards that permit x8 + x8 in the mid range but they tend to be expensive and use PCIe lane multipliers (PLX chip). So to clarify, the PCIe3 slot is an x4 slot. It is an x16 physical slot that is wired as an x4 slot. You can see how the pins in the slot only extend to about a third of the length of the slot vs PCIe1 which has pins all the way to the end. Edited by Xaltar - 24 Feb 2021 at 4:06pm