Slow external SSD

[lucasvc]

I have an external SanDisk SSD rated at up to 800 MB/s read (SanDisk 1TB Portable SSD, Read speeds up to 800 MB/s, USB 3.2 Gen 2, External Solid State Drive, Updated firmware, fastening loop made of durable rubber, Grey : Amazon.co.uk: Computers & Accessories), this is plugged into a USB 3.1 port which should allow it to go at 5 Gbps (625 Mb/s) from the rear IO of an MSI B650 gaming plus WIFI. The problem is that while downloading games of running a benchmark on the drive the highest speed it has ever reached is about 40 MB/s. Does anyone know why it doesn't reach anywhere close to the rated speeds of either the port or the drive?

[Biohazard777]

45 minutes ago, lucasvc said:

either the port or the drive

Judging by reviews on Amazon and SandDisk's site, looks like you are not alone.
People are reporting ~150MB/s and down to ~100MB/s after a while, which is above what USB2 can do, so it isn't a port issue.
Some do report getting the advertised speed, so likely a QC issue.
Yours seems exceptionally bad.

 

In any case, I'd return it.
It ain't cheap, you can get a regular 1TB NVMe + USB3 external enclosure easily for 83 pounds.

[lucasvc]

I considered returning but I have had it for quite a while before I actually started using it and is no longer eligible for return. I have considered trying with a 10Gbps USB C to C cable, in case it is the cable limiting it. 

[MrSimplicity]

USB has never been a great method of data transfer. It keeps getting higher and higher ratings but I've never seen anywhere near rated speeds for any USB standard. Also you have to keep in mind that the "up to" speeds are for the onboard cache in the device. The product page also state that the 800MB/s is read speed and just says "Write speeds lower". So I would just with just using a good C to C cable and just assume that's the best you're gonna get out of it.

 

If you're goal is using for games then I would highly recommend just getting a NVMe drive an external enclosure that has the speeds you're looking for. I had my friend get a 4tb Sabrent NVMe and a ASUS ROG NVMe enclosure and he's been more than happy with it. Obviously you can get a smaller drive than a 4tb but that will net you the speeds that you want for games.

[lucasvc]

I am not quite sure if the SanDisk external drive contains an NVME SSD on the inside. If this is the case would it be reasonable to dismantle it and put the drive on the second M.2 slot I have available?

[MrSimplicity]

8 hours ago, lucasvc said:

I am not quite sure if the SanDisk external drive contains an NVME SSD on the inside. If this is the case would it be reasonable to dismantle it and put the drive on the second M.2 slot I have available?

I'm pretty sure that the SanDisk is not an NVMe given the price for a 1tb. It's basically a fancy looking flash drive. If you have a second m.2 slot then I would just buy a NVMe.