MP 1,1-5,1 PCIE Riser Cable

[ironmanny1]

Hey Guys,

Anyone has any examples of using and securing in place a PCIE Riser cable in their Mac Pro? I have a 6950xt, I want to to put it in slot 1, riser cable in slot 2 to install in a ssd7102.

 

[Matty_TypeR]

you would need a near flush riser cable to sit under the heatsink of the GFX card, as it sits over PCIe 2 slot by about 6mm max. so a right angle riser to fit in pcie slot 2 not one where the cable comes out of the top of the part that fits in pcie 2.

 

[joevt]

Does http://www.adt.link have a solution?
I think you want something like the R11SL-TL, R11SL-FL, or R22SL-TL except an x16 version. There's an R33SL (x16 riser) but it doesn't seem to have a TL version. Maybe you can bend one of the R33 risers enough for your needs. the R33SL has some screws that can be removed from the R3S end which might allow extra bending. Or maybe you can ask for a R33SL-TL.

If you can't get a riser that is low profile enough then you may need to raise up the GPU using something like the R33A but that will probably make the HDMI port of the 6950xt unusable unless you modify the Power Mac somehow.

Another problem is that you won't be able to secure raised PCIe cards using the two thumb screw plate of the Mac Pro (does that thing have a name?). You will have to create something for the PCIe cards to attach to or drill some holes or something.

I used 19mm (0.75 inch) standoffs in the example at #563 but you would need to drill some holes to do that with a Mac Pro.

 

[flyproductions]

Anyone has any examples of using and securing in place a PCIE Riser cable in their Mac Pro? I have a 6950xt, I want to to put it in slot 1, riser cable in slot 2 to install in a ssd7102.

I did just that to get my 6800 in the lowest slot and use a x16 NVMe card to it's full potential.

Pics are beginning with this post in another thread. Cable was Cooler Master, as far as i remember. Shortest length available.

 

[joevt]

I did just that to get my 6800 in the lowest slot and use a x16 NVMe card to it's full potential.

Pics are beginning with this post in another thread. Cable was Cooler Master, as far as i remember. Shortest length available.

That Cooler Master riser works because the 6800 barely intersects with slot 2. It wouldn't work if it were a 3 slot GPU but that's ok for this situation since the 6950xt is also not a three slot card?

The Cooler Master riser attaches to an existing PCI slot which secures the bottom of the PCIe card that connects to it. Is the top of the PCIe card not attached to anything? I suppose it's ok if the PCIe card weight is not too high.

 

[startergo]

6950xt is also not a three slot card

It actually occupies more than 3 slots.
Post in thread 'Success: RX-6800XT in cMP 4,1/5,1'
https://forums.macrumors.com/threads/success-rx-6800xt-in-cmp-4-1-5-1.2344094/post-31083299

 

[flyproductions]

That Cooler Master riser works because the 6800 barely intersects with slot 2. It wouldn't work if it were a 3 slot GPU but that's ok for this situation since the 6950xt is also not a three slot card?

Don't know the exact hight of the 6900. The card could be a little higher/wider as the 6800. But sure not full three slots.

The Cooler Master riser attaches to an existing PCI slot which secures the bottom of the PCIe card that connects to it.

The piece, which secures the riser at the height of the upper PCIe, is DIY. A plastic rail from the hardware store cut to size and attached to the cable with extra strong mounting tape.

Is the top of the PCIe card not attached to anything? I suppose it's ok if the PCIe card weight is not too high.

I elevated the card vs. it's bracket with some also DIY kind of adapter, piece of aluminium rail, for about 20mm. So the card is kept in place securely by the bracket. And no, the upper screwhole is not drilled trough the PCB! I used a countersunk screw which's head does not stick out of the surface of the aluminium.

 

[flyproductions]

It actually occupies more than 3 slots.

If it's more than 3 slots, the PCIe riser will likely not work.

 

[flyproductions]

so a right angle riser to fit in pcie slot 2 not one where the cable comes out of the top of the part that fits in pcie 2.

Don't know, if a thing like that in the very short length needed even exists. And cables coming out the top, i am afraid, could not be bent any sharper than i did. 😕

 

[Matty_TypeR]

This is the only riser cable which might sit under GFX card to allow the use of the PCIe lane.

 

[flyproductions]

This is the only riser cable which might sit under GFX card to allow the use of the PCIe lane.

Don't they come any shorter?

 

[joevt]

This is the only riser cable which might sit under GFX card to allow the use of the PCIe lane.

Google Reverse Image Search gives an AliExpress link.
https://www.aliexpress.com/i/1005002364461314.html?gatewayAdapt=glo2esp

Don't they come any shorter?

5cm appears to be the minimum length. However, sometimes it's easier to bend a longer cable.
Too bad you can't get 0.8 inch (20.32 mm = 2.032 cm) length (minus some amount for non-cable part) to go from one slot to the next.

 

[flyproductions]

5cm appears to be the minimum length. However, sometimes it's easier to bend a longer cable.
Too bad you can't get 0.8 inch (20.32 mm = 2.032 cm) length (minus some amount for non-cable part) to go from one slot to the next.

Sure, a cable with the exact length required will not be available. So, with the cable pointing straight 90º upwards from the slot, as neccessary to clear the GPU's heatsink, a little extra length for a more moderate bend might serve well.

 

[Matty_TypeR]

Just tried one of the cables (post 10) and it works a treat, the cable bends easy and are very well made.

I now have 6950xt in PCIe slot 1 and cable in Pcie slot 2 with StarTech PEX8M2E2 plugged in the cable, giving me 2 = 16X slots, but because 6950xt is in slot 1 i can now fit my usb 3 PCie card into slot 4 and using 3M double sided tape have fitted the riser cable on top of PCIe slot 3. As the StarTech PEX8M2E2 dual M2 card does not need outside access i removed the metal bracket to adjust height to refit in position.

very pleased with the riser cable.

 

[ironmanny1]

Just tried one of the cables (post 10) and it works a treat, the cable bends easy and are very well made.

I now have 6950xt in PCIe slot 1 and cable in Pcie slot 2 with StarTech PEX8M2E2 plugged in the cable, giving me 2 = 16X slots, but because 6950xt is in slot 1 i can now fit my usb 3 PCie card into slot 4 and using 3M double sided tape have fitted the riser cable on top of PCIe slot 3. As the StarTech PEX8M2E2 dual M2 card does not need outside access i removed the metal bracket to adjust height to refit in position.

very pleased with the riser cable.

Thats cool.... can you post a pic of your setup. I've ordered a pcie riser from amazon.... waiting for it to come in.

 

[joevt]

Just tried one of the cables (post 10) and it works a treat, the cable bends easy and are very well made.

Where did you order it from?

 

[Matty_TypeR]

Thats cool.... can you post a pic of your setup. I've ordered a pcie riser from amazon.... waiting for it to come in.

will take some pic's next time i take machine out from under desk, it was ordered from ali express.

Here. https://www.aliexpress.com/item/100...o.order_list.order_list_main.5.41ba18025iP8gQ

 

[ironmanny1]

I've purchased a R33SL 5CM. Slot 1 6950XT Reference Card, Slot 2 PCIE-Riser, Slot 3 Riser on top Connected to SSD7102, Slot 4 USB 3 Card.

I put it together quick and dirty. I need to get some double sided tape for the pcie riser.

 

[startergo]

I've purchased a R33SL 5CM. Slot 1 6950XT Reference Card, Slot 2 PCIE-Riser, Slot 3 Riser on top Connected to SSD7102, Slot 4 USB 3 Card.

I put it together quick and dirty. I need to get some double sided tape for the pcie riser.

Nice. Can you put some photos?

 

[ironmanny1]

Nice. Can you put some photos?

Here you go.

 

[MacNB2]

Here you go.

Great result !
BTW, since you have lost the use of Slot 3, why did not simply fit the SSD card in Slot and the GPU in Slot 2 ?
That's what I do.

 

[Matty_TypeR]

Great result !
BTW, since you have lost the use of Slot 3, why did not simply fit the SSD card in Slot and the GPU in Slot 2 ?
That's what I do.

The reason is with riser cable, GPU in slot 1 x16 riser cable slot 2, both 1&2 are 16x pcie slots, yes you lose slot 3 which riser sits on but it’s only a 4x slot. Slot 4 is still useable.

If you fit GPU in slot 2 6950xt is a 2.5 slot card you lose slots 3 and 4 which are closer together than slots 1 & 2 which then only leaves you slot 1 and 2 useable You gain pcie slot 4 this way but still have your 2 x 16 slots in use.

It works very well 👌

 

[joevt]

Great result !
BTW, since you have lost the use of Slot 3, why did not simply fit the SSD card in Slot and the GPU in Slot 2 ?
That's what I do.

Slot 1 is a double wide slot. Putting the GPU in Slot 2 would not only block Slot 3 but also block Slot 4 like it blocks Slot 2.

If you want to use all slots, then you need 3 risers (for slot 2,3,4) or you need a long riser for slot 2 and position the card in what would be slot 5 (probably blocking drive bay 3 and 4), or you can mount the PCIe card perpendicular to all the other PCIe cards in the space between the PCIe cards and the case cover like where I have these SSDs:
View attachment 1731303
https://forums.macrumors.com/threads/pcie-ssds-nvme-ahci.2146725/page-98?post=29613683#post-29613683

 

[MacNB2]

Slot 1 is a double wide slot. Putting the GPU in Slot 2 would not only block Slot 3 but also block Slot 4 like it blocks Slot 2.

If you want to use all slots, then you need 3 risers (for slot 2,3,4) or you need a long riser for slot 2 and position the card in what would be slot 5 (probably blocking drive bay 3 and 4), or you can mount the PCIe card perpendicular to all the other PCIe cards in the space between the PCIe cards and the case cover like where I have these SSDs:
View attachment 1731303
https://forums.macrumors.com/threads/pcie-ssds-nvme-ahci.2146725/page-98?post=29613683#post-29613683

The RX580 is not 2.5 slot card but it's also not a 2 slot card either...sort of 2.2...just too wide to block Slot 2 slightly if installed in Slot 1.
So in my case, putting it into Slot 2 and my Lycom DT-130 card into Slot 1 still gives Slot 3 and 4 free but of course still loose slots 3 and 4

 

[startergo]

So in my case, putting it into Slot 2 and my Lycom DT-130 card into Slot 1 still gives Slot 3 and 4 free.

If you put in slot 2 (single slot) 2.2 slot card 3 and 4 slots are gone by the same logic