Help with different SSD forms and interfaces please

[katanaqui]

Mostly everything I know about SSDs or RAM here I've basically learned from scratch through a lot of research in the last 48 hours, so simple answers to the following questions would be highly appreciated please!

In short:

1) If they both use a SATA-III interface, is there any difference in speeds between an M.2 form factor SSD and a 2.5" form factor SSD?
I appreciate that different brands/models of SSD will benchmark at different read/write speeds, but I want to confirm that the form factor literally plays no part in this and/or 'real world' performance.

2) Is there a noticeable real world performance difference in an NMVe PCIe2x2 SSD over a SATA-III one? I.e. Do you see a difference in everyday use, and not just in what the read/write scores say.
From what I tell with what my laptop model supports and the few others who have tried it in similar models of the same series, an NVMe PCIe SSD such as the Samsung 960 EVO will top out at around 1700MB/s read/write. I close and load random programs a lot, game but not too heavily (Sims), load/save/simulate in Matlab a lot, and CAD moderately. I also run assistive speech-to-text software that likes to eat RAM over the top of my other programs.

3) Can 2.5" SSDs always use a PCIe interface assuming they're advertised as an NVMe PCIe SSD?
I read something about M.2s being able to use PCIe because they fit directly to the motherboard..? Do 2.5" always fit similarly, do they sometimes need an adapter of some kind? Or might the laptop's slot itself only support up to SATA-III speeds? My noobness really shows here.

---

Laptop details:

I'm buying an ASUS Zenbook UX310UA-FC998R (model strictly non-negotiable). It comes with 8GB RAM and a free memory slot, and a 256GB M.2 SATA-III SSD and a free 2.5" slot. I want to upgrade to 16GB RAM total and a 1TB SSD. I'm currently unsure if either SSD slot supports a PCIe-type interface, and whether the supplied RAM is 8GB soldered + 0GB or 4GB soldered + 4GB replaceable, as neither ASUS or the laptop supplier seem to know for certain. ASUS had 'only tested up to SATA-III in the M.2 slot'.

It also comes with an i7-8500U and I intend in put Win 7 Enterprise 64-bit and Ubuntu LTS 16.04 on it (again, both non-negotiable). I am aware that MS won't support Windows Updates with this CPU and that Win 7 needs extra drivers to support an NVMe SSD. I use Dragon NS Pro (either v12/13, I can't check right now), along with other bits of assistive software.

 

[USAFRet]

1. Same performance. Just a different package.

2. Depending on the particular use case, maybe, maybe not.
For your useage, an NVMe would probably work well and show a noticable difference over SATA III.

3. No.
M.2 is just the physical plugin. It may be SATA III or NVMe. Some systems take one or the other, some either, some differ in which m.2 port.
2.5" SSD's are SATA III.

So it has an m.2 port and a SATA III port.
You need to discover what that specific m.2 port will take.
Any 2.5" SSD will fit in the SATA III location.

 

[katanaqui]

1. Same performance. Just a different package.

2. Depending on the particular use case, maybe, maybe not.
For your useage, an NVMe would probably work well and show a noticable difference over SATA III.

3. No.
M.2 is just the physical plugin. It may be SATA III or NVMe. Some systems take one or the other, some either, some differ in which m.2 port.
2.5" SSD's are SATA III.

So it has an m.2 port and a SATA III port.
You need to discover what that specific m.2 port will take.
Any 2.5" SSD will fit in the SATA III location.

Thank you, your answer is very helpful!

I have one more question for clarification if you don't mind - if 2.5" SSDs are always SATA, then how do ones like the 2.5" NVMe PCIe3x4 Intel 750 SSD work?

 

[USAFRet]

1. Same performance. Just a different package.

2. Depending on the particular use case, maybe, maybe not.
For your useage, an NVMe would probably work well and show a noticable difference over SATA III.

3. No.
M.2 is just the physical plugin. It may be SATA III or NVMe. Some systems take one or the other, some either, some differ in which m.2 port.
2.5" SSD's are SATA III.

So it has an m.2 port and a SATA III port.
You need to discover what that specific m.2 port will take.
Any 2.5" SSD will fit in the SATA III location.

Thank you, your answer is very helpful!

I have one more question for clarification if you don't mind - if 2.5" SSDs are always SATA, then how do ones like the 2.5" NVMe PCIe3x4 Intel 750 SSD work?

Oops, I forgot about that one.
It is a one off.
It is twice as thick (15mm) as a regular SATA III SSD (7mm). Won't fit in a standard laptop.
It uses a U.2 connector.

 

[katanaqui]

1. Same performance. Just a different package.

2. Depending on the particular use case, maybe, maybe not.
For your useage, an NVMe would probably work well and show a noticable difference over SATA III.

3. No.
M.2 is just the physical plugin. It may be SATA III or NVMe. Some systems take one or the other, some either, some differ in which m.2 port.
2.5" SSD's are SATA III.

So it has an m.2 port and a SATA III port.
You need to discover what that specific m.2 port will take.
Any 2.5" SSD will fit in the SATA III location.

Thank you, your answer is very helpful!

I have one more question for clarification if you don't mind - if 2.5" SSDs are always SATA, then how do ones like the 2.5" NVMe PCIe3x4 Intel 750 SSD work?

Oops, I forgot about that one.
It is a one off.
It is twice as thick (15mm) as a regular SATA III SSD (7mm). Won't fit in a standard laptop.
It uses a U.2 connector.

Ah got it, thanks.

Last question (sorry): there seems to be disagreement in whether an NVMe SSD improves Windows boot time. Some say the faster speed = faster boot, others say the nature of an NVMe PCIe means a slower initial boot. Do you know which is the case in general please, and/or if it's much of a difference?

 

[USAFRet]

Ah got it, thanks.

Last question (sorry): there seems to be disagreement in whether an NVMe SSD improves Windows boot time. Some say the faster speed = faster boot, others say the nature of an NVMe PCIe means a slower initial boot. Do you know which is the case in general please, and/or if it's much of a difference?

Overall boot time depends on a lot of other factors.
My current system (500GB 850 EVO boot drive, Win 10 Pro), boots from cold in about 25 secs.
1/2 of that is the BIOS doing its thing. The type of drive has nothing to do with that.
So the actual OS on the drive is 12-13 seconds.

And it also depends on the particular OS and motherboard. Some may be faster, some may be slower.

If an NVMe were to be 50% faster than the existing SATA III drive, that would reduce the overall boot time from 25 secs to 19 secs. The BIOS is still taking up its 12 seconds.
Not nearly enough of a change to worry about.

The NVMe has many other benefits.

My next system will almost certainly have an NVMe drive as the boot drive.