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redneck6497

macrumors member
Original poster
Jul 6, 2009
43
0
Can anyone test an external USB 3.0 HD to their 2015 MBP using the Blackmagic speed test app? I seem to be mostly striking out in that dept. I can't get anything that has any decent speed. I bought a new PNY 3.0 thumb drive. I get around 120 MB/sec read, but maybe 50 or so write. My WD My Passport drive sometimes goes down to 13 writing, and maybe up to a max of 50.

I don't think its the MBP though b/c my MBA has similar results.
 

yjchua95

macrumors 604
Apr 23, 2011
6,725
233
GVA, KUL, MEL (current), ZQN
Can anyone test an external USB 3.0 HD to their 2015 MBP using the Blackmagic speed test app? I seem to be mostly striking out in that dept. I can't get anything that has any decent speed. I bought a new PNY 3.0 thumb drive. I get around 120 MB/sec read, but maybe 50 or so write. My WD My Passport drive sometimes goes down to 13 writing, and maybe up to a max of 50.

I don't think its the MBP though b/c my MBA has similar results.

It's normal. The HDD and the USB stick are too slow to saturate the bus.

On my Transcend 960GB JetDrive USB3 SSD, I get around 400MB/s in both reads and writes.
 

redheeler

macrumors G3
Oct 17, 2014
8,419
8,841
Colorado, USA
Can anyone test an external USB 3.0 HD to their 2015 MBP using the Blackmagic speed test app? I seem to be mostly striking out in that dept. I can't get anything that has any decent speed. I bought a new PNY 3.0 thumb drive. I get around 120 MB/sec read, but maybe 50 or so write. My WD My Passport drive sometimes goes down to 13 writing, and maybe up to a max of 50.

I don't think its the MBP though b/c my MBA has similar results.

As mentioned above, you can't expect the bus to be saturated by a cheap and tiny USB 3 thumb drive. I recall briefly using one as a boot drive, honestly slower than an HDD.

Edit: Same goes for the USB 3 HDD. It's likely only a 5400 RPM also.
 
Last edited:

redneck6497

macrumors member
Original poster
Jul 6, 2009
43
0
As mentioned above, you can't expect the bus to be saturated by a cheap and tiny USB 3 thumb drive. I recall briefly using one as a boot drive, honestly slower than an HDD.

Edit: Same goes for the USB 3 HDD. It's likely only a 5400 RPM also.

I don't think its saturating it for sure, but I'm just wondering if the USB hardware in the mac is working ok. It seems really slow, but I think part of it is the drive itself.

Also, I saw a joke the other day. The Lacie rugged drive with thunderbolt .... why? its a 5400 RPM drive.
 

redneck6497

macrumors member
Original poster
Jul 6, 2009
43
0
It's normal. The HDD and the USB stick are too slow to saturate the bus.

On my Transcend 960GB JetDrive USB3 SSD, I get around 400MB/s in both reads and writes.

I bought a PNY SSD and put it in an OWC case. I mostly got about 250 on read and write ... it did mysteriously go go down to like 110 several times ... not sure why.

I also bought one of the backup Plus units mentioned here also. I got around 110 or 120 out of it.

I think maybe there is something wrong with that WD passport 3.0 drive I have ... no reason for it to go down to like 13.

Does anyone have a super 2.5 USB 3.0 slim enclosure they like for SSDs? I don't know the one I have is so great.
 

yjchua95

macrumors 604
Apr 23, 2011
6,725
233
GVA, KUL, MEL (current), ZQN
I bought a PNY SSD and put it in an OWC case. I mostly got about 250 on read and write ... it did mysteriously go go down to like 110 several times ... not sure why.

I also bought one of the backup Plus units mentioned here also. I got around 110 or 120 out of it.

I think maybe there is something wrong with that WD passport 3.0 drive I have ... no reason for it to go down to like 13.

Does anyone have a super 2.5 USB 3.0 slim enclosure they like for SSDs? I don't know the one I have is so great.
I use an Archgon UASP 2.5" enclosure with USB 3 and get around 430MB/s in both reads and writes, with a 500GB Samsung 850 Evo in it.
 

redneck6497

macrumors member
Original poster
Jul 6, 2009
43
0
That's the exact same enclosure that I use.

Note that you'll only get the speeds that I'm getting if you're using a good SSD.

So after getting the enclosure, there was a modest increase in writes, but a dramatic increase in reads. Now its 424 read and 276 write. Not shabby for an 85.00 SSD.
 
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