Why SSD runs at low speed in the optibay?
I've installed your upgrade kit. And now there is a problem. SSD was installed in Optibay and used as the main drive for OS X. His speed read / write is only 250MB. Why such a low rate? in the information about the system shows that the drive is connected to the speed 6GB. (sata III)
MacBook Pro 15 "Unibody Mid 2012
Thanks for your help!
SSD read speeds are always faster than the write speed. Speeds are noted in MB/s. I think you've confused the size of the SSD with its speed - what did you use to test the read/write speed?
An issue reported by many is that the Macbook Pro seldom boots reliably from an optibay drive when selecting it as primary boot volume. Poor or bad SATA cables and the manufacture of the otpibay kit may be the reason.
By the way this is not iFixit customer service it is the volunteer help forum, so if you want to contact iFixit about a product please use the link at the bottom of the page.
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