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ald0s

macrumors newbie
Original poster
Apr 13, 2022
1
0
Hi folks,
I've checked out the official literature and looked at the pictures, but im having a hard time visualising whether this PCI card setup will find in a 7.1 MP. I've seen pictures of people running dual 6900XTs with room at the bottom - but it'd be nice to get some help.

I want to run the Promise R4i MPX unit in the bottom of the case.

In the top slots I'd like an audio card and a Blackmagic video output. Both are one slot. The BMD card can go in the top half slot.

Can I fit 2 x 6900XT cards in between? I see they vary from 2.5-3 slot designs.

My understanding is the Promise take the bottom 2 PCI lanes (4slots). Do the 2.5 slot 6900 cards cover 3x PCI slots?

-Alex
 

DrEGPU

macrumors regular
Apr 17, 2020
192
82
Not likely. The 6900XT’s will just take up too much space and you’ll have to forgo the audio cards. I forget the name at the moment, but you can get the drive cage that goes above the pcie slots, behind the cpu for more storage. You could put 2x 18TB’s (or even 2x 20TB now!) drives up there for a decent amount drive space. This would allow the 2x 6900XTs in the bottom slots with enough room for the single slot cards above.
 

joevt

macrumors 604
Jun 21, 2012
6,971
4,262
Maybe you can get creative with some PCIe risers and PCIe riser cables to move the slots -- it will be a mess.
https://forums.macrumors.com/threads/thunderbolt-3-m-2-nvme-ssd-enclosures.2027925/post-30814810

That Promise Pegasus R4i MPX takes too much space. There's only 12 PCIe bracket openings (positions). The Radeons only take two openings but they're probably too wide to allow another card to use the adjacent opening? Maybe you could remove the I/O card. You can still get USB and Thunderbolt from the top Thunderbolt ports.

You would need a short riser cable to move Radeon #2 up to position 8. You may need a riser to lift Radeon #1 up to get access to slot 4. Lifting the Radeons might obstruct their top HDMI port. I think each position is 0.8 inches (20.32 mm). I don't know if you can get a riser cable that is low profile enough and short enough to work. Maybe something like this: http://www.adtlink.com/product/R33_ITX.html but the minimum length is 5 cm (the cable would need to be folded if they can't do shorter custom lengths)

Code:
12  slot 8 x4       I/O
11  slot 7 x8       audio/video
10  slot 6 x8       Radeon #2
9   slot 5 x16      Radeon #2
8                   Radeon #2
7   slot 4 x16      Radeon #1
6                   Radeon #1
5   slot 3 x16      Radeon #1
4                   Promise R4i MPX
3   slot 2 x8       Promise R4i MPX
2                   Promise R4i MPX
1   slot 1 x16      Promise R4i MPX

The Promise Pegasus J2i uses space above the I/O card. That would definitely give you enough room.
https://www.promise.com/us/Promotion/PegasusStorage
Code:
12  slot 8 x4       I/O
11  slot 7 x8       audio
10  slot 6 x8       video
9   slot 5 x16      
8                   
7   slot 4 x16      Radeon #2
6                   Radeon #2
5   slot 3 x16      Radeon #2
4                   
3   slot 2 x8       Radeon #1
2                   Radeon #1
1   slot 1 x16      Radeon #1

Or you could add more PCIe slots
https://www.bhphotovideo.com/c/product/980261-REG/dynapower_usa_na255a_xgpu_netstor_6_slot_pcie.html
https://onestopsystems.com/pages/pcie-expansion
 
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joevt

macrumors 604
Jun 21, 2012
6,971
4,262
Just 2x 3.5 inch and 1x 2.5 inch (or 3x 2.5 inch drives, which is what I did).
I'm pretty sure a 2.5 inch is less than half the size of a 3.5 inch so at least 4 of them can fit.
I would prefer to have the dimensions to think up my own hard drive Tetris.
 

DrEGPU

macrumors regular
Apr 17, 2020
192
82
I'm pretty sure a 2.5 inch is less than half the size of a 3.5 inch so at least 4 of them can fit.
I would prefer to have the dimensions to think up my own hard drive Tetris.
There are only 2x sata ports and 1x usb 3 in which to plug in drives. Otherwise, I agree. There’s probably enough space for 5-8X 2.5inch sata drives.
 

joevt

macrumors 604
Jun 21, 2012
6,971
4,262
There are only 2x sata ports and 1x usb 3 in which to plug in drives. Otherwise, I agree. There’s probably enough space for 5-8X 2.5inch sata drives.
In this case, you would use a single slot SATA card which can connect up to 8 drives. This solution would take 3 less slots than the R4i.
And instead of SATA, you can get a card that can connect 8 NVMe drives.
And there are very large capacity 2.5" NVMe drives.
 
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EvilMonk

macrumors 6502
Aug 28, 2006
330
64
Montreal, Canada
Hi folks,
I've checked out the official literature and looked at the pictures, but im having a hard time visualising whether this PCI card setup will find in a 7.1 MP. I've seen pictures of people running dual 6900XTs with room at the bottom - but it'd be nice to get some help.

I want to run the Promise R4i MPX unit in the bottom of the case.

In the top slots I'd like an audio card and a Blackmagic video output. Both are one slot. The BMD card can go in the top half slot.

Can I fit 2 x 6900XT cards in between? I see they vary from 2.5-3 slot designs.

My understanding is the Promise take the bottom 2 PCI lanes (4slots). Do the 2.5 slot 6900 cards cover 3x PCI slots?

-Alex
Take a look at that… https://www.sonnettech.com/product/thunderbolt/duomodo-expansion-systems.html
I’m looking to get one for the new 6,1 Mac Pro deal I got, I’ll have to go the egpu way and I want to hook my 16 bay External SAS NAS to my Mac Pro if I can… this could do both so it’s really interesting ? there’s many options (I want a duo egpu and PCIe expansion but you can go crazy)
Let me know if it’s something you like ??
 

EvilMonk

macrumors 6502
Aug 28, 2006
330
64
Montreal, Canada
In this case, you would use a single slot SATA card which can connect up to 8 drives. This solution would take 3 less slots than the R4i.
And instead of SATA, you can get a card that can connect 8 NVMe drives.
And there are very large capacity 2.5" NVMe drives.
Or this works faster since it’s nvme drives… I have a 16x 3Tb SAS array in raid 6… depends on your needs…
 
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