Gigabyte X670E AORUS Master

[Nopa]

36 - total PCIe lanes (24 CPU+12 chipset)
20 - total usable Gen5 lanes (16+4 on CPU)

If I use a 7950 XTX (PCIe 5.0 x16) and 2 NVMe SSDs (PCIe 5.0 x4) on a B650E MB, will they take those Gen5 lanes from CPU or from the Chipset?

 

[Tek-Check]

If I use a 7950 XTX (PCIe 5.0 x16) and 2 NVMe SSDs (PCIe 5.0 x4) on a B650E MB, will they take those Gen5 lanes from CPU or from the Chipset?

AMD's AM5 chipset Promo21 offers only PCIe 4.0 lanes. CPU offers PCIe 5.0 lanes.
There are two ways to wire this:
1. 16+4+4 from CPU - You will need to make sure that motherboard vendor offers NVMe Gen5 drives that do not share PCIe lanes with any PCIe slot.
2. 8+8 or 8+8+4 - Some boards take PCIe lanes for NVMe drives from the second PCIe slot, which then makes first slot running in x8 Gen5 mode. This shoud not be an issue for AMD's GPU, as x8 Gen5 is plenty of bandwidth.

 

[The Von Matrices]

If there are in total 28 Gen5 lanes on CPU, 4 lanes are for the chipset link and 24 should be usable (16+4+4).

If AMD says "20", does this mean that another x4 Gen5 lanes on CPU cannot be used for Gen5 device?
Shouldn't it be 44/24 and 36/24, or the number "20" refers to minimal requirements?
Is there any motherboard that actually wires 16+4+4 on CPU and uses all 24 Gen5 lanes?

Yes. The board reviewed here has that configuration.

 

[Tek-Check]

Yes. The board reviewed here has that configuration.

Right, indeed. So, AMD's diagram is a minimal requirement.

 

[ir_cow]

I can't rise the memory voltage above 1.435 although for the last 3 bios releases it states that they add memory voltage options over 1.435V. Once I set it to 1.45v it wont post anymore. How do you set it to 1.5v ? Maybe I didn't do it from the right place (first time I have a Gigabyte board) DDR5 voltage control>VDD A0 voltage 1.45.

I didn't have a answer for this because well, I didn't experience this until now. However while working on memory review today, this ONE EXPO kit fails to boot (boots to safety BIOS) if I change the DRAM voltage from auto. I can take another kit and pump 1.5v+ into it, no problem.

 

[The Von Matrices]

There is a weird solution on Aorus Master B650E. Two pairs of M.2 Gen5 drives are attached to x4 interface.

View attachment 268219

That's just the way that Gigabyte has always drawn its chipset diagrams. There's a separate connection to each slot despite there only being one line in the diagram.

 

[Tek-Check]

That's just the way that Gigabyte has always drawn its chipset diagrams. There's a separate connection to each slot despite there only being one line in the diagram.

There is, but if you attach two, both will run in Gen5 x2 mode, as they share the same x4 lanes. Even the spec says that. It's not like that on X670, where two drives occupy two separate x4 buses.

 

[ir_cow]

There is, but if you attach two, both will run in Gen5 x2 mode, as they share the same x4 lanes. Even the spec says that. It's not like that on X670, where two drives occupy two separate x4 buses.

Really? I missed that part. I thought it was 16x split into 8x/4x/4x. I sure didn't get x2 Gen4 speeds when testing. All drives installed at once too. It would top at out 4GB/s if it was really x2.

GB B650E Master

 

[Tek-Check]

Really? I missed that part. I thought it was 16x split into 8x/4x/4x. I sure didn't get x2 Gen4 speeds when testing. All drives installed at once too. It would top at out 4GB/s if it was really x2.

GB B650E Master
View attachment 268495

It is both x16/x4 or x8/x4/x4, or even x8/x2/x2/x2/x2, depending on which slots are used. The diagram below shows that there is a PCIe switch chip installed on x16 bus.

1. x16/x4 usage - we can use GPU in Gen5 x16 mode and ONE NVMe drive in Gen5 x4 mode, if drive is connected to M2A or M2D slot (separate x4 bus).
2. x8/x4/x4 usage - however, x16 slot will drop to x8 mode if one NVMe drive is connected to M2B or M2C slot, as per the spec below.
3. x8/x2/x2/x2/x2 twist - in addition, if both M2B and M2C slots are occupied with NVMe drives, each will run at Gen5 x2 (Gen4 x4) speed ~7 GB/s. The same for M2A and M2D slots.

As each x4 bus serves two NVMe Gen5 drives, Gen5 x4 becomes Gen5 x2 (~7 GB/s) when two drives are linked to one x4 bus or all four occupy two x4 buses.

Your tests exactly revealed what I was trying to explain above. If all four CPU-linked M.2 slots are occupied, each NVMe Gen5 drive will run at Gen5 x2 speed (Gen4 x4), at ~7 GB/s. Gigabyte's diagram from a manual shows that too. There is a pair of M.2 drives hooked to each Gen5 x4 bus.

And Gigabyte's spec for B650E also indicated the same:

Had you installed one NVMe Gen5 drive on each x4 bus, you would have got ~14 GB/s per drive (Gen5 x4 speed). So, each pair of NVMe Gen5 drives share one x4 bus. When there are all four, the chart would look as you posted. It'd be good to edit the main text of the review to make the public aware of this.

 

[ir_cow]

Interesting find. This is important to a review. I missed that whole 2x in the specifications. If I did have Gen5 drives, I would have seen that drop off.

What I don't understand is how gigabyte pulled this off. Gen5 2x doesn't magically turn into Gen4 4x without some extra circuitry. If they're going to go through that effort why not just split the 8x instead of only using half.

 

[Tek-Check]

Interesting find. This is important to a review. I missed that whole 2x in the specifications. If I did have Gen5 drives, I would have seen that drop off.

What I don't understand is how gigabyte pulled this off. Gen5 2x doesn't magically turn into Gen4 4x without some extra circuitry. If they're going to go through that effort why not just split the 8x instead of only using half.

There is a PCIe Gen5 switch chip on x16 bus. That's extra circuitry and it is indicated on Gigabyte's diagram. I added more content in the post above. Have a look.

- config x16/x4 uses 20 lanes from CPU.
- config x8/x4/x4 uses also 20 lanes from CPU, with a twist - x4 'phantom' lanes left unwired on x16 bus.

I suspect that the reason why they did this is that bifurcation of x16 slot on AM5 platform currently allows in BIOS only x8/x8. They did not put effort into splitting remaning x8 lanes into two separate x4 for NVMe drives (BIOS update needed?). Their solution of wiring only one x4 might have been easier and cheaper to implement, for whatever reason. Less Gen5 retimers to protect the integrity of less traces? Protect only four lanes instead of eight?

Could you, please, take a photo of that PCIe Gen5 switch chip if you can, so that we could check its manufacturer and spec?

 

[ir_cow]

We are talking about the B650E Master correct?

 

[Tek-Check]

We are talking about the B650E Master correct?

Yes. All screenshots I posted above are from Gigabyte's official webpage for B650E

 

[ir_cow]

I'll take some pictures later today. What I'm thinking is these are in fact Gen5 4x because they run at Gen4 4x. The way I understand it is PCIe Bifurcation won't change the speed (bandwidth). You need separate chip to turn Gen5 x2 to Gen4 x4. Otherwise a Gen4 device would run at 2x as well. If GB went through the effort of doing that that, might as well just have the two extra lanes.

We will see what chips I find

Edit: Here is a High Rez Link

 

[The Von Matrices]

These are not x2 connections. The footnote is referring to the slots supporting drives with either 4 or 2 lane controllers but there are 4 non-shared lanes in each slot

 

[Tek-Check]

The way I understand it is PCIe Bifurcation won't change the speed (bandwidth). You need separate chip to turn Gen5 x2 to Gen4 x4. Otherwise a Gen4 device would run at 2x as well. If GB went through the effort of doing that that, might as well just have the two extra lanes.

Yes. For your storage throughput chart above, did you attach GPU and all four drives at once in order to get ~7 GB/s on each drive?

These are not x2 connections. The footnote is referring to the slots supporting drives with either 4 or 2 lane controllers but there are 4 non-shared lanes in each slot

I'd like to believe this. If this is the case, Gigabyte's official diagram below is wrong. For B650E, it shows that each pair of NVMe drives share one x4 bus. On X670E, each drive on its own has x4 bus. It does look like four NVMe drives on B650E only have 8 Gen5 lanes at disposal, and not 16, if the diagram is correct.

 

[ir_cow]

Yes. For your storage throughput chart above, did you attach GPU and all four drives at once in order to get ~7 GB/s on each drive?

Yes GPU + 4 Drives at once. They were tested in sequence though. If it was really x2 that wouldn't matter as it would top out at 4GB/s. I think GB just make the diagram easier to read. The X670E is two separate because the 4+4 from the CPU. Same goes for the B650E, but its shows at sharing. Only so much space on a page.

 

[The Von Matrices]

Only so much space on a page.

My thoughts exactly. With the lane-splitting of the x16 slot the page isn't wide enough to show all the slots individually.

 

[Tek-Check]

My thoughts exactly. With the lane-splitting of the x16 slot the page isn't wide enough to show all the slots individually.

They could, at least, do a proper diagram for .pdf file. I mean, c'mon Gigabyte! It's not a brainer.

 

[Gmr_Chick]

I really hate to have to resurrect this thread but I also don't want to create a whole new thread.

I just got this board, and for some reason, the little Creative Pebble speakers I've owned for several years now no longer work....even though they were working on the board that preceded this one, the X670E Hero. I've downloaded the drivers, made sure the audio cable was plugged into the right jack....still no sound. (on the plus side, my RAM runs at its rated EXPO profile now, lol)

Anything else I can try, short of having to buy different speakers?

 

[ir_cow]

These USB speakers or Line-in?

 

[Gmr_Chick]

Nevermind. I got 'em to work again

 

[jesdals]

I have a Logitech 5.1 speaker set that uses 3 jacks for the speakers - any one using this board with a similar speaker setup and how?

 

[ir_cow]

I have a Logitech 5.1 speaker set that uses 3 jacks for the speakers - any one using this board with a similar speaker setup and how?

Install the software. I believe that is the only way to get the other jacks to be setup for 5.1 analog.

You can find more information in the manual.

 

[atm743]

sorry for resurrecting the thread but i've been trying to read block diagrams for the past hour and my head is about to explode lol

im looking to get a X670 board and was looking at the x670e Master or the cheaper X670 AORUS ELITE AX but i have 4 nvme drives. i plan on using all 4 m.2 slots. when doing this, will the top PCI 16X slot drop to 8X when using all m.2 slots? or will it stay on 16x?


by the looks of the block diagram for the Master, it shows PCI express 5.0 bus with the line and having the X16 slot on it as well as 2 M.2 slots both 4X to the cpu. so i would think that using one or both of those m.2 slots would drop the 16X slot to 8X right or am i reading the diagram wrong?

I've been looking at motherboards all night trying to figure out which one to get and i saw that the ASUS ROG STRIX X670E-E GAMING WIFI 6E board will drop the 16X slot to 8X if you use one of the M.2 slots.

from what i see, the ASUS ROG STRIX X670E-F version does not do this but im trying to see if the gigabyte boards do this?

LMK thanks