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Cape Dave

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Original poster
Nov 16, 2012
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SSD in it? If so, does it matter if it is 128, 256 or 512?

In other words, is the quality and speed of the SSD the same, or is it like my iMac 5k where to get the Samsung SSD for sure you had to get the 512GB?

I always like to know what I am getting, BEFORE I get it :)

Thanks, Dave
 
The 13 has a crazy fast SSD but its not the fastest. Currently the 13in SSD has an average speed of 1250MBPS, but the one in the 15in averages 1700MBP. The size of the SSD should not affect the speed like it would in traditional platter drives.
 
The 13 has a crazy fast SSD but its not the fastest. Currently the 13in SSD has an average speed of 1250MBPS, but the one in the 15in averages 1700MBP. The size of the SSD should not affect the speed like it would in traditional platter drives.

Thanks for the FAST reply, you must have an SSD :)

I see now that it does have next generation Flash, but not as fast as the MBPr 15.

Normally, the 128GB size of just about any flash drive is slower than the 512GB version of the same drive. I wonder if that is still true.

Also, anyone know the brand name? Samsung, I hope!
 
Thanks for the FAST reply, you must have an SSD :)

I see now that it does have next generation Flash, but not as fast as the MBPr 15.

Normally, the 128GB size of just about any flash drive is slower than the 512GB version of the same drive. I wonder if that is still true.

Also, anyone know the brand name? Samsung, I hope!

I believe 128GB SSD in the 2015 rMBP is slower than 256GB+ version.
 
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I believe 128GB SSD in the 2015 rMBP is slower than 256GB+ version.

That is what I suspected. That is usually the case with just about any SSD.

I do not need much, but 128 is too confining, so I will get the 256GB.

Unless I sell the iMac 5k and get a MBPr with 2 Retina 21 inch monitors ( We KNOW they are coming), then I will get the 512GB :)
 
128gb has same 1200 gbps read as the 256gb flash, but only 700 gbps write vs around 1200 for the 256gb...enough said.
 
That is what I suspected. That is usually the case with just about any SSD.
The reason that happens is usually due to how the SSD is built internally. If you look at the teardown for an SSD, they're usually made up of a number of identical flash memory chips. Each chip is limited in its read and write speeds. When it's time to read or write data to the chips, the data is spread across multiple chips so instead of limiting you to the speed of a single chip by itself you get combined benefits of reading/writing to multiple chips at once.

Sometimes when they make two models of an SSD where one is twice the space of another they just end up using more of the same flash memory chips which is why you get a speed increase buying the larger drive.

This is a simplified explanation, which might introduce more questions, but in general that's commonly why more space means more speed.
 
The reason that happens is usually due to how the SSD is built internally. If you look at the teardown for an SSD, they're usually made up of a number of identical flash memory chips. Each chip is limited in its read and write speeds. When it's time to read or write data to the chips, the data is spread across multiple chips so instead of limiting you to the speed of a single chip by itself you get combined benefits of reading/writing to multiple chips at once.

Sometimes when they make two models of an SSD where one is twice the space of another they just end up using more of the same flash memory chips which is why you get a speed increase buying the larger drive.

This is a simplified explanation, which might introduce more questions, but in general that's commonly why more space means more speed.

Yes. I knew this to be generally true, but was not sure if it was always true across the board. It makes perfect sense, of course :)

For me, 512GB is the sweet spot where i never have to worry about space. But, it sure does cost more initially. But I think for a laptop, 256 will be fine, and still quite fast enough.
 
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