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I am experiencing very poor SSD writing performance in my Surface Book. It's i5 dGPU 8GB RAM and 256GB storage model. Installing applications and copying files have been really slow. Windows 10 is updated to the latest. Has anyone having the same?
Disabling BitLocker slightly helped (10~20%) but not very much.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
I was having the same issue BUT I found the solution! You should install the Samsung NVM Express Controller. I doubled my write speed to 264MB/s and 96.84MB/S for 4K write.
Download here: http://ssd.samsungsemi.com/ecomobile/ssd/update15.do?fname=/Samsung_NVMExpress_Driver_rev10.zip
I was having the exact problem as OP in the morning, with virtually the same excruciatingly slow 4K write, but rebooted and reran the benchmark and got something a bit more sensible:
This specified symptom may not be a hardware issue per-se, but something in the drivers or firmware. On i5/8GB/dGPU/256GB model.
Microsoft have definitely jibbed us with the PM951 bait and switch (definitely should have been a SM950 level) but the slow write speed issue seems intermittent.
If it keeps happening, sending it back, which would be a great disappointment because it is a great piece of hardware otherwise.
It won't be resolved since this is Microsoft's poor choice of hardware in their premium machine.
For more information, read the review from Anandtech where they explain what happened.
Has this issue been resolved? Any official response from Microsoft?
It seems that the Toshiba Hard Drives are faster - is this right?
Is 512GB the best option for optimum write-speed?
CrystalDiskMark shows 312MB/s 4k write speed.
Not sure why "AS SSD Benchmark" tool is showing ~1MB/sec.
If I make a 10GB file and copy/paste it, its definitely not writing as slow as 1MB per second.
Hey, Jason, welcome to the thread. That AS SSD benchmark, we think, was happening at the same time as some other processes (maybe search indexing, an update, or something) because other drives of the same model are much faster at the 4K write speed.
At the same time...you realize 4K is short for 4KB, right? As in 4 kilobytes? It's the the speed of copying small files. For big files (like your 10GB file), you want sequential speeds (not 4K speeds). If you're doing many many transfers at once, then you should look at QD32 speeds.
Sequential read/write is mostly for copying large files.
4K read/write is mostly for copying very small files (~4KB size)
