MP 1,1-5,1 Two 3.5" drives in lower optical bay (cMP 5,1)?

[macstatic]

Is it possible to fit two 3.5" HDDs in the lower optical drive bay of a cMP 5,1?
I thought I had it covered with a Sharkoon 525 Bayextension. but looking back at an earlier posting of mine I can clearly see in the photos that it only takes a single 3.5" drive but multiple 2.5" devices. There seems to be enough space in the optical "cage" for another 3.5" drive below the one in the photo, but I haven't found any 5.25" adapters for this and I'm a little worried there might be too much heat buildup with two drives so close to each other.

The reason I ask is because I have two "enterprise" HDDs (a 10TB Seagate Exos X10 (ST10000NM0016), and a 12TB Toshiba MG07ACA12TE) which make a lot of noise seek-noises. If I touch the drive or hold it in my hand I can actually feel very strong mechanical movements when it gets busy. This gets transferred through the drive sleds (I had to get the "new screw placement style" trays from OWC for this) and as far as I can tell there's no way to dampen the mechanical vibrations with rubber mounted screws or whatever because the SATA & power connectors have to line up with the backplane.
If I move them over to somewhere else I'll attach them with cables which means I can look into shock-mounting them and thereby lowering the noise levels.

 

[mikas]

That would be an OWC multimount. Unfortunately it's sold out and not coming to catalogues again I think. Maybe it can be found somewhere still. I can't measure it for you with two drives, because I have removed all optical disc drives from all of my 5,1.

 

[arw]

edit: Just saw, your adapter already has 3,5“ decouplers, so ignore my suggestion.
If you could dismiss the optical drive, you could order 2 of these.
https://forums.macrumors.com/thread...-hdd-to-my-2008-mac-pro.2322470/post-30595981
Regarding temperatures: with the drives being helium ones and having the PSU fan, I would be surprised if they came even close to 40°C, even if mounted like in post #2.

 

[macstatic]

That would be an OWC multimount. Unfortunately it's sold out and not coming to catalogues again I think. Maybe it can be found somewhere still. I can't measure it for you with two drives, because I have removed all optical disc drives from all of my 5,1.

That looks like a solution. Too bad it's sold out. I haven't been able to find any so far but will keep looking.
Are those standard sized 3.5" HDDs? If it's not too much trouble, would you mind measuring the various distances as I've outlined below? That would help me to determine if it'll be suitable in my 5,1 lower optical bay with my two drives.

My drives have the "new" type screw layout, and I'm guessing that even if the Multi-mount might not support it I can still mount each drive with just two screws on each side (instead of all three).
By the way, is there any room between each drive when mounted this way, or do they go closely together, touching each other?

 

[mikas]

Sure.

I'd say it's pretty close to 51mm whole package. Space in between would be very very little. You can see through, but it must be less than a millimeter or so.

Height of drives; one inch = 25mm. Heights may vary I think, but this is the most popular height I have read.

I don't think there is a problem with screws on the side of the drive regardless of their capacity. It's the bottom screws which does not necessarily fit. And this adapter has got all three hole positions on it. Start, middle and on end.

 

[macstatic]

Thanks Mikas!
I checked my drives (10TB and 12TB) and they're both 26.1mm high. The adapter might not be suitable for them. What do you think?
So the screw holes on lower and higher capacity drives are the same for the sides but different only from underneath?

 

[macstatic]

edit: Just saw, your adapter already has 3,5“ decouplers, so ignore my suggestion.

What was your suggestion?

If you could dismiss the optical drive, you could order 2 of these.
https://forums.macrumors.com/thread...-hdd-to-my-2008-mac-pro.2322470/post-30595981

I sometimes need to use the DVD drive so I'd rather not remove it. It would indeed make this a lot simpler though. In worst case I'll just install one of the drives in the lower optical bay and that would be the Time Machine backup (Toshiba 12TB) as it gets very busy (meaning noisy) whenever it takes backups. The main drive doesn't seem to get so busy with normal use, but is just as noisy when it does.
I wish there was something I could do with a drive mounted in the regular drive bay.

Regarding temperatures: with the drives being helium ones and having the PSU fan, I would be surprised if they came even close to 40°C, even if mounted like in post #2.

I had forgotten about them both being helium-filled, and you're right about the power supply fan being in the close proximity. Good news!

 

[mikas]

That would be a really tight fit I think. There would be absolutely no gap in there. The upper one of the drives can be taller though, if the OD bay is tall enough, because it grows out of the bracket, upwards. I think you get it.

But I think it would fit, I took another pic. It would be 26 and some fractions of a millimeter between the holes. I would say pretty close to 26.1mm.

 

[macstatic]

Hmmm.... tricky stuff
I think I'll have to spend some time on this and see if I can come up with a creative solution. Apart from the optical bay and the normal drive bays, there aren't any other places to mount a 3.5" drive (cMP 5,1)?

If I end up being able to shock mount only a single 3.5" drive I'll have to drill two extra holes in my Sharkoon adapter (to allow the "new" style HDD) and that should take care of half the problem (i.e. one out of two noisy drives).

 

[arw]

What was your suggestion?

The link I left anyway. It's just for a single 3,5" drive.

Apart from the optical bay and the normal drive bays, there aren't any other places to mount a 3.5" drive (cMP 5,1)?

1. If you have free PCI slots, there are brackets to mount a 3,5" HDD there. I haven't found any with decouplers, so you'd have to widen the holes and insert grommets yourself.
2. If you are handy and wild enough: It's possible to position the two HDDs besides each other in the optical bay, rotated by 90°s. It would involve cutting/modifying the original cage to fit the SATA connectors and figuring out a custom, dampened mounting solution.
I'd then definitely move the ROM drive to the lower bay to have easier access to the drives from above.
3. If you have 2 free HDD slots, figure out a way to mount your adapter to an original sled, rotated by 90°s and use a SATA extension cable to connect it.
edit: added picture to suggestion 3

 

[macstatic]

Cool! I didn't know about those PCI brackets. I found one here which takes two 2.5" drives or one 3.5" drive:

Several other good suggestions you have there as well.

I haven't given up the optical bay yet though, and time permitting I'm going to see if there's enough vertical room for two "new" style large capacity 3.5" drives stacked on top of each other or not. If there's enough room I'm thinking a metal plate sort on each side to join them together with screws, then a hole on each side matched with the 5.25" mounting holes inside the lower optical bay so that spacers (with rubber damping) can be attached.
With a metal workshop this could probably be easily done, but as I have no access to that I need to look into more readily available solutions (or easily modifiable with simpler tools).