I want to write a followup on the problem I was having with my Amfeltec Squid x4. I wrote about this on July 17 here in this thread but the problem had persisted ever since and it was frustrating to watch and wait for the spinning wheel to disappear each time I shutdown my MP5,1, which usually would go on endlessly.
During the past month, I did two things: One, I had a hunch that the problem was a cache related issue and, after sifting through them in System folder, I discovered that throwing away System/Library/Caches/com.apple.coresymbolicationd/data helped produce a smooth shutdown. Two, when I tried the Lycom DT-120 in place of Squid, this adapter worked fine and the shutdown sequence proceeded normally. Also at one point my MP5,1 produced intermittent I/O errors and I was sure there was something strange going on with the Squid card and I guessed that my Mac would try to record all errors in the cache file but was unable to write them, or something like that.
Recently I had a chance to buy another Squid adapter for another machine and this time I decided to get a x16 model and experimented it on my machine and voila! This card worked perfectly in the same slot #3. Obviously the difference was in the spec, x16 against my earlier x4, but this time Amfeltec sent me a card with a cooling fan attached to the inner end of the card. They also included four heat sinks in the box which adhered to four SSD blades (SM951 512GB AHCI).
They call their current Squid card Gen.3 and I must assume the people at Amfeltec have addressed the heat issue and upgraded their product accordingly. I don't know if these cooling devices are included with their current x4 card but if anyone is seeing similar symptoms, I would strongly recommend getting a Gen.3 adapter. Now that I want to move on to Sierra soon, I’m going to replace my card in the next few weeks.
Sorry, if this is an old news.
