PCI-E 4 in 1 USB Riser vs MB with lots of PCI-E x1 slots

[michnern]

Just investigating GPU mining and wondering if anyone could recommend some good PCI-E 4 in 1 risers with decently long USB cables. I found these but the cable is only just under 2ft long and that may not be long enough for the outer cards.

https://www.amazon.com/Ubit-Riser-Adapter-Powered-Extension/dp/B0746H1KY3/


Also, is there an advantage of going with the MB's that support 12 - 19 GPUs instead of just buying PCI-E 4 in 1 risers that work with any Motherboard? Do GPUs suffer performance wise from having 4 GPUs share a single PCI-E x1 slot instead of having a dedicated PCI-E x1 slot each?

Thanks,

[R0land]

Just investigating GPU mining and wondering if anyone could recommend some good PCI-E 4 in 1 risers with decently long USB cables. I found these but the cable is only just under 2ft long and that may not be long enough for the outer cards.

You can use this hub: https://www.amazon.de/XCSOURCE%C2%AE-Multiplier-Erweiterungs-Stromanschluss-AC817/dp/B072VBK3GD/ref=sr_1_9?ie=UTF8&qid=1513285284&sr=8-9&keywords=pcie+hub

[Undefined31415]

Also, is there an advantage of going with the MB's that support 12 - 19 GPUs instead of just buying PCI-E 4 in 1 risers that work with any Motherboard? Do GPUs suffer performance wise from having 4 GPUs share a single PCI-E x1 slot instead of having a dedicated PCI-E x1 slot each?

The advantage to going with motherboards that support 12+ GPUs is that those exist.

PCIe 4-in-1 risers that work with "any motherboard" do not exist. Moreover, trying to use several on the same motherboard is asking for setup headaches, unless you happen to get exceedingly lucky with your choice of motherboards.


For mining on the vast majority of algorithms, PCIe bandwidth will make no measurable difference.

Another thing to consider is that more than 12 cards in one rig might not be desirable, as it is quite a large number of eggs in the same basket.

[michnern]

Also, is there an advantage of going with the MB's that support 12 - 19 GPUs instead of just buying PCI-E 4 in 1 risers that work with any Motherboard? Do GPUs suffer performance wise from having 4 GPUs share a single PCI-E x1 slot instead of having a dedicated PCI-E x1 slot each?

The advantage to going with motherboards that support 12+ GPUs is that those exist.

PCIe 4-in-1 risers that work with "any motherboard" do not exist. Moreover, trying to use several on the same motherboard is asking for setup headaches, unless you happen to get exceedingly lucky with your choice of motherboards.


For mining on the vast majority of algorithms, PCIe bandwidth will make no measurable difference.

Another thing to consider is that more than 12 cards in one rig might not be desirable, as it is quite a large number of eggs in the same basket.

Thanks for the reply.... Can you explain why the Ubit PCI-E 4 in 1 riser from Amazon I linked in my first post wouldn't work in any motherboard that has a PCI-E x1 slot? What kind of issues could you run into?

Thanks again.

[DevelopmentBank]

What a coincidence i was also looking to buy one of these to repurpose one of my older motherboards with only 3 PCIE slots. Like the OP, i too am worried about compatibility and stability of my rig with these installed.

Correct me if i'm wrong but does buying these PCIE extenders just entail luck (whether or not it will be compatible to your board) or is there a data sheet we can use as reference for compatibility?

[Undefined31415]

Also, is there an advantage of going with the MB's that support 12 - 19 GPUs instead of just buying PCI-E 4 in 1 risers that work with any Motherboard? Do GPUs suffer performance wise from having 4 GPUs share a single PCI-E x1 slot instead of having a dedicated PCI-E x1 slot each?

The advantage to going with motherboards that support 12+ GPUs is that those exist.

PCIe 4-in-1 risers that work with "any motherboard" do not exist. Moreover, trying to use several on the same motherboard is asking for setup headaches, unless you happen to get exceedingly lucky with your choice of motherboards.


For mining on the vast majority of algorithms, PCIe bandwidth will make no measurable difference.

Another thing to consider is that more than 12 cards in one rig might not be desirable, as it is quite a large number of eggs in the same basket.

Thanks for the reply.... Can you explain why the Ubit PCI-E 4 in 1 riser from Amazon I linked in my first post wouldn't work in any motherboard that has a PCI-E x1 slot? What kind of issues could you run into?

Thanks again.

I have personally used that Ubit device with an MSI 970A-g43 (2 x16, and 2 x1 slots) to run 6x 1060s. However, 7 cards consistently failed to boot, no matter what I tried.

Regardless of the number of physical slots a motherboard has (or how many you "make" it have using splitters & whatnot), the number of physical slots available doesn't necessarily tell you how many graphics cards will actually work in the system. It's not a simple as looking at the number of physical PCIe slots, or even allowed PCIe lane configurations from the CPU & chipset information. This is why the PCIe splitters are so hit-and-miss.

In short, motherboards tend to have their own limits that PCIe splitters provide no guarantee of bypassing.

https://bitcointalk.org/index.php?topic=1795879.80
(Pardon all the garbage.)

[michnern]

Also, is there an advantage of going with the MB's that support 12 - 19 GPUs instead of just buying PCI-E 4 in 1 risers that work with any Motherboard? Do GPUs suffer performance wise from having 4 GPUs share a single PCI-E x1 slot instead of having a dedicated PCI-E x1 slot each?

The advantage to going with motherboards that support 12+ GPUs is that those exist.

PCIe 4-in-1 risers that work with "any motherboard" do not exist. Moreover, trying to use several on the same motherboard is asking for setup headaches, unless you happen to get exceedingly lucky with your choice of motherboards.


For mining on the vast majority of algorithms, PCIe bandwidth will make no measurable difference.

Another thing to consider is that more than 12 cards in one rig might not be desirable, as it is quite a large number of eggs in the same basket.

Thanks for the reply.... Can you explain why the Ubit PCI-E 4 in 1 riser from Amazon I linked in my first post wouldn't work in any motherboard that has a PCI-E x1 slot? What kind of issues could you run into?

Thanks again.

I have personally used that Ubit device with an MSI 970A-g43 (2 x16, and 2 x1 slots) to run 6x 1060s. However, 7 cards consistently failed to boot, no matter what I tried.

Regardless of the number of physical slots a motherboard has (or how many you "make" it have using splitters & whatnot), the number of physical slots available doesn't necessarily tell you how many graphics cards will actually work in the system. It's not a simple as looking at the number of physical PCIe slots, or even allowed PCIe lane configurations from the CPU & chipset information. This is why the PCIe splitters are so hit-and-miss.

In short, motherboards tend to have their own limits that PCIe splitters provide no guarantee of bypassing.

https://bitcointalk.org/index.php?topic=1795879.80
(Pardon all the garbage.)

Thanks, that elaboration made complete sense. In short, the motherboard has to be designed from the get go to support X number of PCI-E x1 slots. Looking at the Asus B250 MB for example that has 18 or 19 PCI-E x1 slots and is made for mining, it's obvious that board has a lot of customizations in the BIOS specific to mining which other non mining customized BIOSs may complain about or fail.

Thanks again,