Pcie x16 problems

[OutsaneIngenuity]

Budget (including currency): n/a

Country: us

Games, programs or workloads that it will be used for: n/a

Other details (existing parts lists, whether any peripherals are needed, what you're upgrading from, when you're going to buy, what resolution and refresh rate you want to play at, etc):

 

I will be getting the asus maximus dark hero for a new build but am confused about its memory restrictions. It says that if the m.2_1 position is in use it will knock down the pcie slot to x8 instead of x16. Then later in a different spot it doesn't specify that it's the m.2_1 position it just says m.2 is in use. I tried calling Asus and they were as confused as i am. Trying to get clarification on if I can plug in a gpu and put m.2s in the other slots and it will be fine or if I need to get a pcie storage. Plugging in a pcie won't cause the same issue they will both stay at x16 right? Does m.2 have the same position requirements like ram does? Cpu will be i9.13900k probably getting a 4090 gpu unless they announce something better within the next few months

 

Thanks everyone for the help! I will make another forum with my full build once I'm done and put the link here. If you would like to see or double check it you're all welcome to!

Edited January 27 by OutsaneIngenuity
Thanks

[RONOTHAN##]

3 minutes ago, OutsaneIngenuity said:

I will be getting the asus maximus dark hero for a new build but am confused about its memory restrictions.

Why are you getting this board? It rarely makes any sense, since it's worse than the Z790 Apex Encore that's $50 cheaper and the vast majority of people will be more than happy with a $200-300 board like the Z790 Aorus Elite X. 

 

5 minutes ago, OutsaneIngenuity said:

It says that if the m.2_1 position is in use it will knock down the pcie slot to x8 instead of x16

That is correct, the two x16 slots and the first M.2 slot share bandwidth. Unless you are using a Gen 5 SSD, you want to use M.2_2 for your SSD, and even then, if you are using a Gen 5 SSD you should be going Ryzen 7000 instead. 

[OutsaneIngenuity]

19 hours ago, RONOTHAN## said:

Why are you getting this board? It rarely makes any sense, since it's worse than the Z790 Apex Encore that's $50 cheaper and the vast majority of people will be more than happy with a $200-300 board like the Z790 Aorus Elite X

When I compared the two I didn't see any benefits for the encore that stuck out. Also it's white and I am not a fan of that lol. This is a passion project so i want a higher shelf board so no reason to get a 2-300$

[RONOTHAN##]

6 minutes ago, OutsaneIngenuity said:

Also it's white and I am not a fan of that lol.

You weren't looking at the Encore:

https://rog.asus.com/motherboards/rog-maximus/rog-maximus-z790-apex-encore/

 

It's the extreme overclocking board from ASUS, it has arguably the best VRM on any Z790 motherboard, has the best memory support of any Z790 motherboard in terms of frequency, dual BIOS, and as many buttons and switches as you can hope for. The only thing the Dark Hero has going for it is built in TB4, and that can be had with an add in card resulting in a better version of Thunderbolt anyway as you can inject the DP signal from the GPU rather than using the iGPU. 

[OutsaneIngenuity]

19 hours ago, RONOTHAN## said:

That is correct, the two x16 slots and the first M.2 slot share bandwidth. Unless you are using a Gen 5 SSD, you want to use M.2_2 for your SSD, and even then, if you are using a Gen 5 SSD you should be going Ryzen 7000 instead.

Okay so as long as i put an m.2 in the 2nd slot i should be fine then? I'll probably get a gen 5 ssd as i will move large files occasionally. I thought I'd have to put it in the pcie to avoid making them x8 so was looking at a gigabyte aorus but m.2 would be simpler. I don't know much of anything about AMD which is why I'm sticking with Intel as I've been waiting to build this for forever already. I've also already bought the cpu lol

[OutsaneIngenuity]

9 minutes ago, RONOTHAN## said:

You weren't looking at the Encore:

https://rog.asus.com/motherboards/rog-maximus/rog-maximus-z790-apex-encore/

 

It's the extreme overclocking board from ASUS, it has arguably the best VRM on any Z790 motherboard, has the best memory support of any Z790 motherboard in terms of frequency, dual BIOS, and as many buttons and switches as you can hope for. The only thing the Dark Hero has going for it is built in TB4, and that can be had with an add in card resulting in a better version of Thunderbolt anyway as you can inject the DP signal from the GPU rather than using the iGPU. 

I haven't purchased the motherboard yet so I'm not against switching, however I'm not an IT so once things get beyond plugging in and turning on xmp and maybe a little extra overlooking I'm out of my depth. What is dual bios for? How would you add in tb4? what kind of card?

[RONOTHAN##]

Just now, OutsaneIngenuity said:

I'll probably get a gen 5 ssd as i will move large files occasionally.

How large? It's not likely to make a difference though. 

 

Gen 5 SSDs only really have a benefit in peak bandwidth, their random performance isn't that much better than Gen 4 SSDs, so it only really makes a noticeable improvement when you're moving files >1GB in size and over 100GB in total, and even then it takes 8-9 seconds rather than 13-14 seconds. Big deal. Besides, if you want to use a Gen 5 SSD on Intel at Gen 5 bandwidth, the GPU will be running at x8. There's no way to prevent that. 

 

You can use a Gen 5 SSD and have the GPU at x16, only AMD allows that currently. 

 

2 minutes ago, OutsaneIngenuity said:

What is dual bios for?

Two main reasons. If your BIOS chip fails for whatever reason, you have a spare so the board isn't bricked, and (more likely the reason it exists on this board) you can compare two BIOS revisions to see what is better for your particular use case. 

 

12 minutes ago, OutsaneIngenuity said:

How would you add in tb4? what kind of card?

https://www.asus.com/us/motherboards-components/motherboards/accessories/thunderboltex-4/

Get a card like this and you have Thunderbolt 4 support. Whether or not you actually need it is up for debate. 

[AlfaProto]

On 1/14/2024 at 9:28 AM, OutsaneIngenuity said:

I will be getting the asus maximus dark hero for a new build but am confused about its memory restrictions. It says that if the m.2_1 position is in use it will knock down the pcie slot to x8 instead of x16. Then later in a different spot it doesn't specify that it's the m.2_1 position it just says m.2 is in use. I tried calling Asus and they were as confused as i am. Trying to get clarification on if I can plug in a gpu and put m.2s in the other slots and it will be fine or if I need to get a pcie storage. Plugging in a pcie won't cause the same issue they will both stay at x16 right? Does m.2 have the same position requirements like ram does? Cpu will be i9.13900k probably getting a 4090 gpu unless they announce something better within the next few months

 

ASUS, another company that doesn't uses BLOCK DIAGRAM like Gigabyte.


Read further below on Graphics card installation:

The M.2 notes:

 

The break down:

The First Column: You only have 1 GPU installed, no M.2 on M2_1. This GPU will run at full x16 speeds.

The Second Column: You have 2 GPUs installed, no M.2 on M2_1. Both GPU will run at x8 speeds.

The Third Column: You only have 1 GPU install AND M.2 on M2_1. This GPU will run at x8 speeds and M.2 get x4 speeds. The Second PCIE x16 is disabled.

 

The THIRD COLUMN, why is your GPU running at x8 speeds? Let's take a look at Z790/CPU block diagram by Intel:

 

Do you see that 1x16 PCIE 5.0 OR 2x8 PCIE 5.0? Your M2_1 is using PCIE 5.0 lanes, instead of the dedicated 1x4 PCIE 4.0 lanes.

 

However, it doesn't show the WHOLE PICTURE. If you have PCIE 4.0 card and PCIE 5.0 SSD. Your SSD will NOT run at PCIE 5.0 speeds, it will run at PCIE 4.0 speeds, due to the fact that your PCIE 4.0 card is the slowest.

[OutsaneIngenuity]

17 hours ago, AlfaProto said:

ASUS, another company that doesn't uses BLOCK DIAGRAM like Gigabyte.


Read further below on Graphics card installation:

The M.2 notes:

 

The break down:

The First Column: You only have 1 GPU installed, no M.2 on M2_1. This GPU will run at full x16 speeds.

The Second Column: You have 2 GPUs installed, no M.2 on M2_1. Both GPU will run at x8 speeds.

The Third Column: You only have 1 GPU install AND M.2 on M2_1. This GPU will run at x8 speeds and M.2 get x4 speeds. The Second PCIE x16 is disabled.

 

The THIRD COLUMN, why is your GPU running at x8 speeds? Let's take a look at Z790/CPU block diagram by Intel:

 

Do you see that 1x16 PCIE 5.0 OR 2x8 PCIE 5.0? Your M2_1 is using PCIE 5.0 lanes, instead of the dedicated 1x4 PCIE 4.0 lanes.

 

However, it doesn't show the WHOLE PICTURE. If you have PCIE 4.0 card and PCIE 5.0 SSD. Your SSD will NOT run at PCIE 5.0 speeds, it will run at PCIE 4.0 speeds, due to the fact that your PCIE 4.0 card is the slowest.

So if I have a graphics card installed and an m.2 in the second slot the graphics card will run at x16 and the m.2 will function normally then right?

[OutsaneIngenuity]

On 1/14/2024 at 2:30 PM, RONOTHAN## said:

How large? It's not likely to make a difference though. 

 

Gen 5 SSDs only really have a benefit in peak bandwidth, their random performance isn't that much better than Gen 4 SSDs, so it only really makes a noticeable improvement when you're moving files >1GB in size and over 100GB in total, and even then it takes 8-9 seconds rather than 13-14 seconds. Big deal. Besides, if you want to use a Gen 5 SSD on Intel at Gen 5 bandwidth, the GPU will be running at x8. There's no way to prevent that. 

 

You can use a Gen 5 SSD and have the GPU at x16, only AMD allows that currently. 

 

Two main reasons. If your BIOS chip fails for whatever reason, you have a spare so the board isn't bricked, and (more likely the reason it exists on this board) you can compare two BIOS revisions to see what is better for your particular use case. 

 

https://www.asus.com/us/motherboards-components/motherboards/accessories/thunderboltex-4/

Get a card like this and you have Thunderbolt 4 support. Whether or not you actually need it is up for debate. 

Honestly not particular about gen 5 ssd so if getting gen 4 makes my graphics card function fully that's no problem. As far as size I usually try to have 4+ Tb of space as it fills up very quickly (I have a LOT of portable ssd's v.v) my goal is essentially to have everything running fully but it's been so confusing with everything sharing bandwidth.

[brob]

5 hours ago, OutsaneIngenuity said:

Honestly not particular about gen 5 ssd so if getting gen 4 makes my graphics card function fully that's no problem.

 

It has nothing to do with the PCIe generation and everything to do with which m.2 slot is used. If M2_1 is occupied any card in PCIEX(G5)_1 wil only have 8 lanes.

[AlfaProto]

17 hours ago, OutsaneIngenuity said:

So if I have a graphics card installed and an m.2 in the second slot the graphics card will run at x16 and the m.2 will function normally then right?

Yes, as long as you installed your SSD under M2_2 or the other one, your GPU will run at full x16.

 

M2_2 uses the dedicated 4 PCIE gen4 lanes.

 

The M2_3 to _5 uses the chipset lanes.

[OutsaneIngenuity]

7 hours ago, AlfaProto said:

Yes, as long as you installed your SSD under M2_2 or the other one, your GPU will run at full x16.

 

M2_2 uses the dedicated 4 PCIE gen4 lanes.

 

The M2_3 to _5 uses the chipset lanes.

Thank you. What are the chipset lanes?

[Queen Chrysalis]

Just curious, and to better contextual all of this, what are you using this PC for primarily?

[AlfaProto]

5 hours ago, OutsaneIngenuity said:

Thank you. What are the chipset lanes?

 

The full block diagram of Z790 chipset as shown above. 20 PCIE 4.0 lanes from the chipset.

 

 

The M.2s from the chipset uses total 12 PCIE 4.0 lanes.

ASUS should publish their block diagram like Gigabyte.

 

[OutsaneIngenuity]

On 1/16/2024 at 11:26 PM, Queen Chrysalis said:

Just curious, and to better contextual all of this, what are you using this PC for primarily?

Gaming, streaming/recording, and graphic art. Also working on setting up some 3d modeling but that's still in the works

[OutsaneIngenuity]

On 1/17/2024 at 4:44 AM, AlfaProto said:

 

The full block diagram of Z790 chipset as shown above. 20 PCIE 4.0 lanes from the chipset.

 

 

The M.2s from the chipset uses total 12 PCIE 4.0 lanes.

ASUS should publish their block diagram like Gigabyte.

 

Okay so that's the bandwith from the motherboard kinda. I would be fine then putting m.2s in the 3-5 slots then as long as they were gen. 4s and each only needs x4 right? Does them using the chipset lanes effect anything else vs the 2nd slot?

[AlfaProto]

2 hours ago, OutsaneIngenuity said:

Okay so that's the bandwith from the motherboard kinda. I would be fine then putting m.2s in the 3-5 slots then as long as they were gen. 4s and each only needs x4 right?

Yes, M2_3 to M2_5 are gen 4, and all are full x4 lanes, as stated in its own manual.

2 hours ago, OutsaneIngenuity said:

Does them using the chipset lanes effect anything else vs the 2nd slot?

The manual doesn't state much, I know some other motherboard will disable 2 SATA ports, because that one M.2 slot shared with 2 SATA ports.

 

However, since ASUS stated it's accepts only PCIE SSD, and not SATA+PCIE SSD, it's safe to assume that SATA ports aren't affected.

[QuantumSingularity]

Even if because of the M.2_1 slot your PCIe gen 5 slot is running in x8 mode, you will have absolutely no trouble with that, because the fastest GPU, the - 4090 is PCIe Gen 4, which is half of Gen 5 speed. To make it perfectly clear the throughoutput of x8 Gen5 = x16 Gen 4. 

 

With all that said, i perfectly agree with the people above - that motherboard is not worth it and there are far better and cheaper boards. And if you want Gen 5 utilization and compatibility, you should turn to AMD and Ryzen 7000.

[brob]

PCIe lanes run at the highest speed COMMON to both ends. A PCIe 4 GPU in a PCIe 5 slot will run at PCIe 4. If the slot only provisions 8 lanes then the GPU will run 8x PCIe 4.

[Queen Chrysalis]

14 hours ago, OutsaneIngenuity said:

Gaming, streaming/recording, and graphic art. Also working on setting up some 3d modeling but that's still in the works

Yeah, so like, this stuff will be cool for like 5 minutes after you’ve configured it, but other than that this all a major exercise in excess.  I know you said it’s a passion project, but like, you’re just buying stuff.

[OutsaneIngenuity]

On 1/18/2024 at 10:07 AM, QuantumSingularity said:

Even if because of the M.2_1 slot your PCIe gen 5 slot is running in x8 mode, you will have absolutely no trouble with that, because the fastest GPU, the - 4090 is PCIe Gen 4, which is half of Gen 5 speed. To make it perfectly clear the throughoutput of x8 Gen5 = x16 Gen 4. 

 

With all that said, i perfectly agree with the people above - that motherboard is not worth it and there are far better and cheaper boards. And if you want Gen 5 utilization and compatibility, you should turn to AMD and Ryzen 7000.

Whaaaaaaa! I thought the 4090 was the best gpu currently (unless they make a 4090 super). What's up with that, the gpu is 1/2 as strong as the slot? As far as price goes im not worried because this is a passion project I've saved for so I was/am just trying to build the best pc I can (gaming/streaming/graphic arts/animation). However I already bought an i9-13900k. unless there is a better board than the dark hero or encore?

[OutsaneIngenuity]

18 hours ago, Queen Chrysalis said:

Yeah, so like, this stuff will be cool for like 5 minutes after you’ve configured it, but other than that this all a major exercise in excess.  I know you said it’s a passion project, but like, you’re just buying stuff.

Im confident there will be occasions I push it towards its limit. And hey, it's cheaper than building a car. Gotta be efficient with your dopamine per dollar ratio and not all of us won the lottery on our allotted categories. That aside it comes with the sweet benefit of when I get blamed for a "hardware" issue I can list my specs and tell them to pound sand! (This happens more than you'd think and every time the issue has not been on my end)

[OutsaneIngenuity]

On 1/18/2024 at 8:13 AM, AlfaProto said:

Yes, M2_3 to M2_5 are gen 4, and all are full x4 lanes, as stated in its own manual.

The manual doesn't state much, I know some other motherboard will disable 2 SATA ports, because that one M.2 slot shared with 2 SATA ports.

 

However, since ASUS stated it's accepts only PCIE SSD, and not SATA+PCIE SSD, it's safe to assume that SATA ports aren't affected.

So someone else just notified me that the 4090 is gen 4 and x8 gen5 is the same as x16 Gen 4..... makes me sad asf and now I have to re-question my build. If that is the case is there even anything to take advantage of x16 Gen 5? 

[-rascal-]

On 1/14/2024 at 12:58 PM, RONOTHAN## said:

You weren't looking at the Encore:

https://rog.asus.com/motherboards/rog-maximus/rog-maximus-z790-apex-encore/

 

It's the extreme overclocking board from ASUS, it has arguably the best VRM on any Z790 motherboard, has the best memory support of any Z790 motherboard in terms of frequency, dual BIOS, and as many buttons and switches as you can hope for. The only thing the Dark Hero has going for it is built in TB4, and that can be had with an add in card resulting in a better version of Thunderbolt anyway as you can inject the DP signal from the GPU rather than using the iGPU. 

 

I'm just so confused with ASUS' line-up of "ROG" boards these days, and the insanely high price premium for "ASUS" and "ROG".

They were not like this prior to.... 2017?

 

From top -> bottom

• Apex / Encore
• Extreme
• Formula
• Hero
• Impact (ITX board)
• StriX

The -Hero tier was the "budget" ROG line-up, if you didn't want the "High OC" boards.

How is the Apex / Encore CHEAPER than the Hero these days....