Gigabyte Z490 Vision D (Thunderbolt 3) + i5-10400 + AMD RX 580

[dehjomz]

I apologize if this has been asked already. With the Vision-D Z490 Board, If I were to upgrade to a 11900K Processor to enable PCIe4 support, will this fully enable the PCIe4 Spec on the motherboard? Namely, will the M2A_CPU M.2 socket reroute to CPU PCIE Lanes? Currently with the 10900K the M2A_CPU is using the Z490 chipset lanes according to the spec in the manual. I assume the 16x and 8x PCIe slots move to the faster PCIe4 lane speed.

I am debating if it is worth the upgrade. My crazy thought is it would be nice to maybe double up the GPU's, since PCIe4 x8 slot are equal to PCIe3 x16 slot. From there run Hypervisor and have both Windows and MacOS running simultaneously on the same box each with their own discreet graphics.

When you add a Rocket Lake CPU to the Z490 Vision D, there is an option in the BIOS that enables you to use the top M.2 slot as direct attached CPU lanes. This option did not exist in earlier BIOSes.

Comet Lake only had 16 CPU-attached PCIe lanes but Rocket Lake has 20, 16 for the graphics card, 4 for a direct-CPU attached M.2 slot.

I forgot the name of the specific option in the BIOS as my Z490 Vision D has been retired. But I tested it, and it worked. I tested on the F20 BIOS, and it was not enabled by default.

It should be also noted that in order to use Rocket lake, you need at least BIOS F20 as the earlier BIOSes don’t support Rocket Lake.

 

[scottkendall]

I concede that the M2A_CPU designation is strange, but as shown in the block diagram it comes from the PCH, from the PCH only, and it has to come from the PCH to be able to use SATA lanes.
You may hope that there's some undisclosed trickery to make the best of Rocket Lake CPUs—and I'd be happy to be proven wrong on documentation reading.

Personal experience with undisclosed features: The Asus P10S WS motherboard has a 5-pin Thunderbolt header (TBT), which is not mentioned anywhere in the manual. I could not get the motherboard to recognise any Asus or Gigabyte Thunderbolt AIC connected to it, and no known trick could get Thunderbolt drivers to load under Windows or a Thunderbolt section to appear in the BIOS. It looks like Asus engineers tried and failed to implement Thunderbolt, and that marketing and documentation tried to hide any intent to implement Thunderbolt, although the board is manufactured with a neatly labelled header.

I drew diagrams all the time for work; that does not mean I do not leave out information I find to be conflicting with my intended purpose for the diagram. That said just because it goes to the PCH does not mean that there is not as you say Trickery. I am not a Electrical Engineer; but, maybe just maybe, when you put the 11 gen CPU in, maybe it routes the drive as I show in this revised diagram:

 

[dehjomz]

I drew diagrams all the time for work; that does not mean I do not leave out information I find to be conflicting with my intended purpose for the diagram. That said just because it goes to the PCH does not mean that there is not as you say Trickery. I am not a Electrical Engineer; but, maybe just maybe, when you put the 11 gen CPU in, maybe it routes the drive as I show in this revised diagram:

View attachment 542002

This topology was necessary for Comet Lake because it only had 16 direct CPU lanes. So not enough for a x16 graphics card plus an X4 M.2 slot.

But Intel upgraded the pipe with Rocket Lake and added 20 direct CPU lanes, 16 for graphics and 4 for M.2.

So the Z490 Vision D has a PCIe switch; with Comet Lake it uses the PCH with the top M.2 slot, and with the upgraded pipe of Rocket Lake, it can switch to using direct CPU lanes for the top M.2 slot.

However, as of F20, you have to explicitly select an option in the BIOS to enable the vision d to use the 4 direct CPU lanes from Rocket Lake, otherwise by default the mobo will default to using the PCH with that top M.2 slot.

 

[tyns]

This topology was necessary for Comet Lake because it only had 16 direct CPU lanes. So not enough for a x16 graphics card plus an X4 M.2 slot.

But Intel upgraded the pipe with Rocket Lake and added 20 direct CPU lanes, 16 for graphics and 4 for M.2.

So the Z490 Vision D has a PCIe switch; with Comet Lake it uses the PCH with the top M.2 slot, and with the upgraded pipe of Rocket Lake, it can switch to using direct CPU lanes for the top M.2 slot.

However, as of F20, you have to explicitly select an option in the BIOS to enable the vision d to use the 4 direct CPU lanes from Rocket Lake, otherwise by default the mobo will default to using the PCH with that top M.2 slot.

Exactly, 10th gen only has 16 CPU Lanes so that M2A_CPU needed to be routed to the chipset lanes by design. Thank you so much for your input. I am still waiting for a response from Gigabyte's support team to be absolutely sure. The BIOS enabler for the M.2 reroute to CPU is definitely good to hear! I will check it out.

 

[tyns]

Found this as well:
https://www.gigabyte.com/de/Press/News/1870

 

[dehjomz]

Exactly, 10th gen only has 16 CPU Lanes so that M2A_CPU needed to be routed to the chipset lanes by design. Thank you so much for your input. I am still waiting for a response from Gigabyte's support team to be absolutely sure. The BIOS enabler for the M.2 reroute to CPU is definitely good to hear! I will check it out.

What more is there to be sure about? F20 supports it. Just find the Rocket Lake support setting for the top M.2 slot, turn it on, and enjoy PCIe 4.0.

 

[sardino]

Hello! So after a couple of months, I decided to install Windows to make my system dual boot. I’ve been able to install windows following @CaseySJ instructions in page 191 and everything went smooth. Windows booted straight from its NVMe. Then I changed disk boot order in BIOS to choose as first option the Mac disk. When I get to OpenCore, I can see the Windows disk there but it doesn’t start. Sometimes I get a black screen sometimes preparing automatic repair…in BIOS, if I choose the windows disk, it works. I also been able to boot into Windows by choosing the Windows drive in system preferences/startup disk while on Mac, but this only worked once. If I do it now, I just get to the black screen or the preparing automatic repair message. Do I need to change something in BIOS?

Thanks in advance.

 

[CaseySJ]

Hello! So after a couple of months, I decided to install Windows to make my system dual boot. I’ve been able to install windows following @CaseySJ instructions in page 191 and everything went smooth. Windows booted straight from its NVMe. Then I changed disk boot order in BIOS to choose as first option the Mac disk. When I get to OpenCore, I can see the Windows disk there but it doesn’t start. Sometimes I get a black screen sometimes preparing automatic repair…in BIOS, if I choose the windows disk, it works. I also been able to boot into Windows by choosing the Windows drive in system preferences/startup disk while on Mac, but this only worked once. If I do it now, I just get to the black screen or the preparing automatic repair message. Do I need to change something in BIOS?

Thanks in advance.

Please have a look at the first section of the OpenCore 0.7.8 mini-guide. There’s a link in that section for turning off AppleVTD.

By the way, which M.2 slot is the Windows disk installed in?

 

[sardino]

Please have a look at the first section of the OpenCore 0.7.8 mini-guide. There’s a link in that section for turning off AppleVTD.

By the way, which M.2 slot is the Windows disk installed in?

It is installed in the slot closest to the CPU.
I’ll have a look at your mini guide.
I am so thankful…you are always willing to help.

 

[sardino]

Thank you @CaseySJ I followed your instructions, and now everything works as supposed. I have another little problem, I have to pair my Magic Mouse, Magic Keyboard and TrackPad when I switch from Mac to Windows and vice versa…any hints?
Thanks again.