Late 13 drive sizes and number of PCIE lanes

[CASLondon]

Hi

I'm looking to clarify how the rMBP late 13 Samsung pcie flash drives compare.

I understand the 1TB connects at 4 lanes. I own a rMBP with a 512g that connects at 2 lanes.

Is that number of lanes from the drive, or the connection/cable? If I pull that drive out for a 1TB, it will run at 4 lanes at greater r/w speed?

If I use that 512g in another machine with a 4 lane adapter, is it limited to 2 lanes or will it be able to connect at 4 lanes?

Thanks.

 

[konradsa]

Hi

I'm looking to clarify how the rMBP late 13 Samsung pcie flash drives compare.

I understand the 1TB connects at 4 lanes. I own a rMBP with a 512g that connects at 2 lanes.

Is that number of lanes from the drive, or the connection/cable? If I pull that drive out for a 1TB, it will run at 4 lanes at greater r/w speed?

If I use that 512g in another machine with a 4 lane adapter, is it limited to 2 lanes or will it be able to connect at 4 lanes?

Thanks.

My understanding is that the drive tells the controller how many PICe lanes it wants to use. So yes, putting a 1 TB drive in your machine should use 4 lanes, and in another machine the 512 GB drive will use two lanes. The reason is that the 1 TB drive is faster, since it has twice the memory chips. So it can saturate more lanes.

But that performance advantage may be something you only see in benchmarks rather then every day use. I would not replace my 512 GB drive with 1 TB just for the higher transfer rates. Besides, I have a 256 GB drive, and I think that one is already wicked fast.

 

[yjchua95]

Hi

I'm looking to clarify how the rMBP late 13 Samsung pcie flash drives compare.

I understand the 1TB connects at 4 lanes. I own a rMBP with a 512g that connects at 2 lanes.

Is that number of lanes from the drive, or the connection/cable? If I pull that drive out for a 1TB, it will run at 4 lanes at greater r/w speed?

If I use that 512g in another machine with a 4 lane adapter, is it limited to 2 lanes or will it be able to connect at 4 lanes?

Thanks.

It's the drive itself.

Some people have tried putting in a 4-lane 512GB extracted from an nMP into an rMBP and have confirmed that it works at speeds of around 1GB/s.

 

[CASLondon]

thanks for the clarification