How to build your own iMac Pro [Successful Build/Extended Guide]

[dwhitla]

Nope! PCIEX_1_1 disables 802.11ad and PCIEX_1_2 and PCIEX16_4 disable SATA ports! Give it a try yourself. Only PCIEX16_1, PCIEX16_2 and PCIEX16_3 can be populated without disabling either 802.11ad or SATA ports in consequence..

Wrong. I am using all SATA ports. PCIEX_4 only shares lanes on a 16 or 28 lane CPU. Yours and mine are both 44 lane CPUs.

 

[kgp]

Regardless the TB3 only needs 4 lanes. Putting it in slot 3 is a waste of a 16 lane slot that is meant for a GPU.

If I don't put any card in slot 3, I waste 16 lanes

I just have 1 GPU, the OSXWifi and the Thunderbold EX 3. Once more, this is not a general advice that all users should use this configuration! The topic was what to do in case one just has these 3 PCIe cards ! It might help to avoid the OsxAptioFixDrv-64.efi memory allocation error, if the latter is related at all!

If you have 2 GPUs it is obvious that you won't waste slot 3 with the Thunderbold EX 3!

 

[dwhitla]

This is why advised people to only use 7900X or high on this mainboard.

 

[dwhitla]

If I don't put any card in slot 3, I waste 16 lanes

I just have 1 GPU, the OSXWifi and the Thunderbold EX 3. Once more, this is not a general advice that all users should use this configuration! The topic was what to do in case one just has these 3 PCIe cards ! It might help to avoid the OsxAptioFixDrv-64.efi memory allocation error, if the latter is related at all!

If you have 2 GPUs it is obvious that you won't waste slot 3 with the Thunderbold EX 3!

And I'm telling you it can't be a factor because I am using every PCIEX16 slot and every SATA port and every M.2 slot.
I was also just pointing out that it is silly to put a 4 lane card in a 16 lane slot when there is a 4 lane slot free.

 

[kgp]

This is why advised people to only use 7900X or high on this mainboard.

Yup, but that has nothing to do with the i7-7800 or i7-7820 or any Skylake-X CPU below. It is also not a question of available lanes. I can confirm the same ASUS Prime X299 Deluxe behaviour in case of the i9-7980XE:

• PCIEX_1_1 disables 802.11ad
• PCIEX_1_2 and PCIEX16_4 disable SATA ports!

Nothing to do against this behaviour I guess. Or did you find some BIOS settings to manually prevent the else automatic disabling?

 

[kgp]

And I'm telling you it can't be a factor because I am using every PCIEX16 slot and every SATA port and every M.2 slot.
I was also just pointing out that it is silly to put a 4 lane card in a 16 lane slot when there is a 4 lane slot free.

Why silly? As long I do not need the 16 lane slot for a 16 lane card, why I would not be able to plug a 4 lane card? I don't understand the point of the entire discussion, sorry...

 

[dwhitla]

I can confirm the same ASUS Prime X299 Deluxe behaviour in case of the i9-7980XE:

• PCIEX_1_2 and PCIEX16_4 disable SATA ports!

This is absolutely not correct. Only PCIEX_1_2 shares lanes with SATA using that CPU.

 

[kgp]

This is absolutely not correct.

Unfortunately it is... at least on my board with 0802.. what can I do?

 

[dwhitla]

Why silly? As long I do not need the 16 lane slot for a 16 lane card, why I would not be able to plug a 4 lane card?

You can - but you will be tying up 16 lanes and only using 4.

 

[dwhitla]

Unfortunately it is... at least on my board with 0802.. what can I do?

My BIOS is 0802 also. No SATA ports disabled as per my slot allocation above.