I remember reading a lot of speculation about this, but I'm not sure there was a clear conclusion. A dominant hypothesis was that big drives may take slightly longer to spin up. The boot routine may time out if it does not immediately detect a drive on the SATA 2 bus, so moves on until it finds a system. Drives connected via native USB 2 are not a problem because this interface is designed to detect when a new device is attached. But SATA 2 is not hot swapable, so perhaps if a drive is not detected in time, it never will be. Cold boot may provide more time before the boot sequence looks for the drives, so less chance of missing it.
I know that was a problem for many people. In my case the usual solutions (eg taping the pin with kapton) didn't help. PWDIS also doesn't readily explain why the drives were booting fine during a cold restart.
I had this problem with a 10TB WD drive. I taped up pin 3 to get it working in the Mac Pro. it would mount on cold boot but would not survive a warm reboot.
According to the link in post #43:
But it's above my understanding how that could be the case as my disks don't spin down and I even hear/feel the reading head move before the OC boot picker is displayed. And yet they are invisible to the Mac.
I do not recommend this approach.
He means it won't recognize the drives after a restart (warm boot), but if the machine is off and booted (cold boot) it *will* recognize them normally.
Hi Soba, I know from experience that proper gaffers tape will hold, even if it will get hot. But you have to use real Gaffa tape, preferably from a brand like Nichiban not a fake one like duct tape. The difference is described here:
Exactly, and probably when not combined in a soft raid they will show up in a warm boot. I’ve heard that it has to do with the drives/raid not showing up fast enough when warm booting to be recognized. My other 10TB drive is normally recognized on a warm boot.
Thanks for responding. Yeah I know it’s looks ‘crazy’ to use Gaffa tape, but you would be surprised how often tape is being used in high-end applications nowadays. And I don’t want to spend money just for cosmetical reasons while this works perfectly. Remember, the drives are still in place by two screws, the tape is just to hold the drives ‘up’ and it does the trick great. Personally being a fan of DIY solutions I prefer to stick 😉 with this method, but anyone is free to do otherwise.
POST = Power On Self TestI think "POST" stands for Pre-Operating-System-Test (or maybe Pre-Os-Self-Test). Either way you finally have a 'precisely correct' answer to the question posed above..
COLD BOOT runs "POST"
WARM BOOT does *not* run "POST"
Amazing huh! I tripped across this paragraph earlier this morning so I am happy I could help
Thanks - makes senses so if that is truly the only delta, then the questions now are: (a) can it be fixed; or (b) is there any way to have the POST run even know there is no power-on event? I believe both are doubtful - "A" because I believe POSTs reside in true-ROM and "B" because I would bet that code is hardwired to only get accessed during an actual power-on event with no other way to trigger its execution...
Both models of Seagate 5TB and 6TB that I shucked from external USB drives have the standard screw arrangement and work correctly.
I remember reading due to the additional sealing requirements all helium drives moved said holes away from the middle.
