Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Moof1904

macrumors 65816
Original poster
May 20, 2004
1,060
102
I have an OWC Accelsior S PCI card with an Intel SSD mounted on it and ever since I installed it (in slot 7), it spontaneously keeps dismounting itself, causing the "Disk Not Ejected Properly" message. It doesn't seem to be linked to any particular behavior (e.g., it's not happening only at wake), it's just happening. This latest time it just happened about 30 minutes after I woke the computer and started doing other stuff (stuff not involving that volume).

Is this a Catalina problem (drives dismounting spontaneously)?
Is this a problem with the OWC card itself?
Is this a problem with the PCI slot?

Barring any additional insights from the collective, my options are to begin a painstaking process of trying different PCI slots, different SSD's, different computers (I have a 2008 Mac Pro I could put it in), to try and isolate the cause, but I wanted to start with a query here in case someone has some insights that could help.

Thanks.
 
I have an OWC Accelsior S PCI card with an Intel SSD mounted on it and ever since I installed it (in slot 7), it spontaneously keeps dismounting itself, causing the "Disk Not Ejected Properly" message. It doesn't seem to be linked to any particular behavior (e.g., it's not happening only at wake), it's just happening. This latest time it just happened about 30 minutes after I woke the computer and started doing other stuff (stuff not involving that volume).

Is this a Catalina problem (drives dismounting spontaneously)?
Is this a problem with the OWC card itself?
Is this a problem with the PCI slot?

Barring any additional insights from the collective, my options are to begin a painstaking process of trying different PCI slots, different SSD's, different computers (I have a 2008 Mac Pro I could put it in), to try and isolate the cause, but I wanted to start with a query here in case someone has some insights that could help.

Thanks.
First, I’d take the card out of the system, remove the drive, and inspect the connectors (PCI and drive). Then reseat the drive, double-checking it’s completely inserted, and do the same with the card. Reseating everything is always the first action with these kinds of problems.

Second, it looks like that card doesn’t come in a 0G configuration. Do you still have the original drive? If so, put it back in the card and see if the problem persists with that drive. That will help you isolate the source of the problem.

[edit] I now see there’s a 0G config on the upper right corner of the product page for $47.99, so scratch my latter point if that’s what you bought.
 
Last edited:
Do you have the power settings to let the computer sleep or spin down drives. I would try disabling those settings and see if it makes a difference. Some cards and drives cannot handle the Mac sleeping
 
  • Like
Reactions: OkiRun
I have an OWC Accelsior S PCI card with an Intel SSD mounted on it and ever since I installed it (in slot 7),

If you go to the tech spec and compatibility tabs at OWC site ( pick one of the configurations with a SATA SSD attached and dive down into the stats).

This is an 'older' card ( x2 PCI-e v2 ) and the new Mac Pro 2019 isn't listed as a compatible system. While the listing for the card says "Mac OS X 10.6 and up" that may just be a fragment left from "long long ago" that hasn't been updated. If the Asmedia 1062 controller isn't actively supported still then you'll have issues.

If go to OWC site for SSDs for the Mac Pro


and dive down into the 2019 model, you won't find that card. The card list has an "ASMedia ASM2824" which is far newer than that. ( It handles PCI-e SSDs but even if look at other OWC products that handle SATA 1062 is pretty old. )


Barring any additional insights from the collective, my options are to begin a painstaking process of trying different PCI slots, different SSD's, different computers (I have a 2008 Mac Pro I could put it in), to try and isolate the cause, but I wanted to start with a query here in case someone has some insights that could help.

Thanks.

The SATA SSDs shouldn't matter too much but can try putting the original in if still have it. The other consideration is firmware for the SSD also. ( not sure what 'updater" path Intel has. If there is no Mac updater then they probably haven't tested extensively on Macs. ).
 
It does come in a 0 TB config. That's how I bought this one, just a week or so ago. It's the $47.99 version that's shown on the default order button. So, there is no "original" drive to try.

I'm thinking that y'all are right that its design is too old to be compatible with the 7,1. I'll pull it and put it in the 2008 Mac Pro and save my $$$ for something more compatible.
 
Do you have the power settings to let the computer sleep or spin down drives. I would try disabling those settings and see if it makes a difference. Some cards and drives cannot handle the Mac sleeping
Yup ~
One of the first configurations I made on the 7.1 was to disable computer sleeping. I've had no problems with any hardware or software. I also do not power off the computer at night. Screensaver is set after an hour. I do not let the monitor sleep either.
 
Last edited:
I had this problem with the OWC 2010-2012 8TB ACCELSIOR M2 Card. I ended up returning it for other reasons but before that I moved it to a different PCIe slot and the problem went away.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.