02-10-2019 09:12 AM
greetings, according the the compatibility checker, the MX500 is supposed to be compatible with the imac 9,1
the imac 9,1 has a sata II nvidia mcp79 chipset and is apparently finicky with some drives. if there's an issue, usually the drive connects at sata I speed.
i've noticed that sometimes the mx500 shows it is connected at sata II speeds but at other times, it connects at sata I speeds. is this a sign on incompatibility?
is there a risk of data loss or corruption because of this?
02-10-2019 10:29 AM - edited 02-10-2019 10:32 AM
There's no risk of data corruption since the issue affects the sata speed negotiation during initial connection routine between the drive and the host and has no subsequent effect (other than lower speed) when the drive is actually in use. When faced with a sata 3 drive it will use 1 instead of the 2 it would be using if nvidia had written the handshake correctly.
02-11-2019 09:49 PM
thanks for the reply.
one strange thing i noticed, if i cold boot the imac 9,1 from the power button, the link speed will be set to SATA I but if i then restart the imac from within OSX, the sata link speed gets set to SATA II. this seems to happen every time (it's repeatable). as long as no data is lost or corrupted, i could probably live with this.
02-11-2019 10:01 PM
Try an Option boot. Maybe if you give it a little more time to communicate before the OS loads maybe it can negotiate the faster link speed. If this works, then maybe you can do a PRAM reset which will unselect the Startup Disk. Without the Startup Disk being selected the system will take a little extra time to determine the boot drive which could be all you need.