What hdd caddy?

[CoastalOR]

My optical bay does do 6gb/s - and so does the hgts 1tb 7200rpm hdd - so does that mean they will connect at 6gb/s?

Yes, you MIGHT be able to connect at 6gb/s, but NO, you will not see 6gb/s throughput.

snaky69 said on post #24: "Some 2011 will refuse to do SATA III (6Gbps) in the optical bay. Since you're planning on using a platter hard drive, it doesn't matter one bit. A mechanical hard drive can't even saturate SATA I (1.5Gbps)."
Your hgst 1tb 7200 drive is a platter (mechanical) hard drive so it is the bottleneck. While the optical bay 6gb/s port and adaptor may be capable of 6gb/s (see my comment below), the hgts 1tb 7200rpm hdd does NOT do 6gb/s. The hgts 1tb 7200rpm hdd will not even do 1.5gbps.

In case you do not belive snaky69, here is another source saying there is a possibility of speeds slower than 6gb/s. Check out the 2nd link I provided in post #2 and scroll down to the red text near the bottom of the page. Here is an excerpt from that text (BTW, you have MacBook Pro Model ID 8,1):
"Testing has demonstrated that Apple factory hardware does not reliably support a 6G (6Gb/s) Solid State Drive or Hard Disk Drive in the optical bay of 2011 MacBook Pros (Model ID 8,1; 8,2; 8,3)."

 

[tomf]

Yes, you MIGHT be able to connect at 6gb/s, but NO, you will not see 6gb/s throughput.

snaky69 said on post #24: "Some 2011 will refuse to do SATA III (6Gbps) in the optical bay. Since you're planning on using a platter hard drive, it doesn't matter one bit. A mechanical hard drive can't even saturate SATA I (1.5Gbps)."
Your hgst 1tb 7200 drive is a platter (mechanical) hard drive so it is the bottleneck. While the optical bay 6gb/s port and adaptor may be capable of 6gb/s (see my comment below), the hgts 1tb 7200rpm hdd does NOT do 6gb/s. The hgts 1tb 7200rpm hdd will not even do 1.5gbps.

In case you do not belive snaky69, here is another source saying there is a possibility of speeds slower than 6gb/s. Check out the 2nd link I provided in post #2 and scroll down to the red text near the bottom of the page. Here is an excerpt from that text (BTW, you have MacBook Pro Model ID 8,1):
"Testing has demonstrated that Apple factory hardware does not reliably support a 6G (6Gb/s) Solid State Drive or Hard Disk Drive in the optical bay of 2011 MacBook Pros (Model ID 8,1; 8,2; 8,3)."

Ok thanks I'll have a look, I did check my system info and it said 6gb/s for my optical drive. But if the hgst drive can't do sata 3 then ok.
What I don't understand is why does the hgst says it does sata 3 6gb/s?

 

[CoastalOR]

Ok thanks I'll have a look, I did check my system info and it said 6gb/s for my optical drive. But if the hgst drive can't do sata 3 then ok.
What I don't understand is why does the hgst says it does sata 3 6gb/s?

Why not stick to one thread? You have been given information by asking the same questions in your "MacBook Pro really lagging" thread and simonsi (post #62) has already answered this question and other questions that you also asked here. I think working both threads are leading to your confusion and wasting our time. I'm done.

 

[snaky69]

Ok thanks I'll have a look, I did check my system info and it said 6gb/s for my optical drive. But if the hgst drive can't do sata 3 then ok.
What I don't understand is why does the hgst says it does sata 3 6gb/s?

It simply means that it can connect at that speed. It doesn't mean you'll get that speed in actual usage. Just like you can connect USB 3.0, 2.0 and 1.1 in the same port, they'll all work. They'll work at the speed of the slowest link in the chain.

The speeds are measured in GigaBITS not GigaBYTES. 1 byte = 8 bits.

6 Gigabits = 0.75 Gigabytes, or 750MB.
1.5 Gigabits(AKA SATA I) = 187,5 MB.

A traditional hard drive can maybe, in the best possible conditions, do 125MB/s read and write or so.

That means that no matter the SATA version used, you'll notice absolutely zero difference between them.

If you were to stick an SSD in there, that's another matter entirely.