options to add motherboard slots

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philb2

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What are practical options for adding card slots to a motherboard?

My ASUS ROG X670E Strix-E motherboard has only 3 card slots: 2 x16 and 1 x 1

The x16 slots are used for the GPU card and a SATA port extender card. That leaves just 1 X1 slot, which I use for more USB A and USB C ports, which can't even operate at full speed on X1. I woulld like to have say 2 x4 slots, so I could also add an adapter for a USB 3 twin header for USB 3 case ports.

EDIT: 2 x 16 and 1 x 1.
 
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The Zen 4 desktop CPUs don't support bifurcation on any existing motherboard. You can split the first x16 lanes from the CPU into two physical x8 / x8 slots, but you can't split the second physical x8 slot into x4 / x4 to add say two NVMe drives. You have to use a PCIe adapter for whatever peripheral you need that uses a PCIe switch ship.

I would just buy a HEDT system like Sapphire Rapids or Threadripper with 64 or 128 PCIe lanes. I can easily run 5.2 GHz on 8 cores on my Xeon W7, with 6000 MT/s C28 memory.
 
philb2 said:
What are practical options for adding card slots to a motherboard?
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Literally none on your platform. Desktops nowadays don't often use add-in cards other than the GPU. But if you have a use case for more connectivity, you think ahead and you buy a platform with enough PCIe lanes provided and enough slots for your use case. It doesn't make sense to purchase a CPU and motherboard, then think "oh shucks it doesn't support the connectivity I need". If for your usage you're going to need a lot of PCIe, can you get by on a consumer platform with a motherboard that supports PCIe bifurcation? Or do you need to go HEDT/server with more PCIe lanes and slots?

Monstieur said:
The Zen 4 desktop CPUs don't support bifurcation on any existing motherboard. You can split the first x16 lanes from the CPU into two physical x8 / x8 slots, but you can't split the second physical x8 slot into x4 / x4 to add say two NVMe drives. You have to use a PCIe adapter for whatever peripheral you need that uses a PCIe switch ship.

I would just buy a HEDT system like Sapphire Rapids or Threadripper with 64 or 128 PCIe lanes. I can easily run 5.2 GHz on 8 cores on my Xeon W7, with 6000 MT/s C28 memory.
Click to expand...

Well stated.
 
Monstieur said:
The Zen 4 desktop CPUs don't support bifurcation on any existing motherboard. You can split the first x16 lanes from the CPU into two physical x8 / x8 slots, but you can't split the second physical x8 slot into x4 / x4 to add say two NVMe drives. You have to use a PCIe adapter for whatever peripheral you need that uses a PCIe switch ship.
Click to expand...
I really appreciate this explanation.

Monstieur said:
I would just buy a HEDT system like Sapphire Rapids or Threadripper with 64 or 128 PCIe lanes. I can easily run 5.2 GHz on 8 cores on my Xeon W7, with 6000 MT/s C28 memory.
Click to expand...
I can't just buy a Threadripper system, and a new motherboard. I just dropped a bundle on the X670e motherboard, a 7900x CPU, and 64 GB of RAM. Oh, and a new 850 W power supply. She Who Must Be Obeyed would never go along with a Threadripper upgrade now. Maybe when it's time to upgrade, which for me is about 4-5 years away.
 
If you can find an AM5 mobo with Thunderbolt ports, you could indirectly add more PCIe slots that way. Some B550 and X570S boards had TB3/4, dunno abt AM5.

Otherwise, yeah HEDT for lots of PCIe.
 
If you have an open m.2 slot, you might be able to jigger something up. If you want USB, there's an m.2 to dual USB 3.0 header adapter on amazon, and I vaguely recall seeing some way to use an m.2 slot to drive a PCIe card.
 
philb2 said:
That leaves just 1 X1 slot, which I use for more USB A and USB C ports, which can't even operate at full speed on X1.
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Is that a typo ?

I would feel your third slot should be at least x4 Gen4, 8GB/s which should support a lot 10Gbps usb 3.2 connection.
https://dlcdnets.asus.com/pub/ASUS/mb/Socket AM5/ROG_STRIX_X670E-E_GAMING_WIFI/E21210_ROG_STRIX_X670E-E_GAMING_WIFI_UM_V3_WEB.pdf?model=ROG STRIX X670E-E GAMING WIFI


One possibility could be to consider a NAS for the slow SATA connection (assuming SATA is being for harddrives) if that would be possible and leave the fast direct on the machine PCIe for the USB devices.

That board start with 12x USB 3.2 in back, 1x 2x2 + 1 2x2, 1 3.2 gen 1 at the front, you can probably easily add 8 with the PCIE to go over 20, after using hub for USB stuff that can afford to be slow to leave room for the many gig a second affair.
 
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NattyKathy said:
If you can find an AM5 mobo with Thunderbolt ports, you could indirectly add more PCIe slots that way. Some B550 and X570S boards had TB3/4, dunno abt AM5.

Otherwise, yeah HEDT for lots of PCIe.
Click to expand...
Yeah, I'm afraid you're right. Maybe I need to buy some lottery tickets or wait for some rich uncle to die, the uncle I never had of course.
 
LukeTbk said:
Is that a typo ?

I would feel your third slot should be at least x4 Gen4, 8GB/s which should support a lot 10Gbps usb 3.2 connection.
https://dlcdnets.asus.com/pub/ASUS/mb/Socket AM5/ROG_STRIX_X670E-E_GAMING_WIFI/E21210_ROG_STRIX_X670E-E_GAMING_WIFI_UM_V3_WEB.pdf?model=ROG STRIX X670E-E GAMING WIFI
Click to expand...

That's exactly the board I have.
LukeTbk said:
One possibility could be to consider a NAS for the slow SATA connection (assuming SATA is being for harddrives) if that would be possible and leave the fast direct on the machine PCIe for the USB devices.

That board start with 12x USB 3.2 in back, 1x 2x2 + 1 2x2, 1 3.2 gen 1 at the front, you can probably easily add 8 with the PCIE to go over 20, after using hub for USB stuff that can afford to be slow to leave room for the many gig a second affair.
Click to expand...
I'm not understanding this, but I appreciate your effort putting together this post.

Aree you sayin that I should remove the SATA ports card and put the HDDs in a NAS? For two of those HDDs, I use them a lot and I would hate to suffer a speed loss.
 
philb2 said:
Aree you sayin that I should remove the SATA ports card and put the HDDs in a NAS?
Click to expand...
Yup, obviously if you need more than 4 sata port (4 port board goes quicker than the traditional 6 one) that could not be an option (specially if the network is only 1gbps).

There adapter that do both, (4xusb 3 and 2xsata):
https://www.amazon.ca/Syba-Chipsets-Standard-Brackets-SD-PEX50064/dp/B00MVTB7Q4?th=1
That could maybe do the trick if you can use some slower usb 3 port and just 2 sata in extra.
 
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