# How many M.2 SSDs can I fit?



## Dalkamyr (Jan 16, 2017)

A) If I have a z170 motherboard with a i7 6700k, how many m.2 SSDs can I put on my mobo without forcing my graphics card to go down to x8?

B) And if I do let it go down to x8, how many can I fit? 

C) Let's say I have 2x nvidia cards in sli which I want to run at 16x/16x plus two M.2 SSDs and a high end sound card. 

Which motherboard/cpu combinations would allow me to do the "C)" scenario?


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## newtekie1 (Jan 16, 2017)

Most Z170 motherboards have the M.2 ports run off the PCI-E lanes provided by the PCH.  The graphics slots use slots coming from the CPU.  So adding an M.2 drive will not affect the lanes going to the GPUs.



Dalkamyr said:


> C) Let's say I have 2x nvidia cards in sli which I want to run at 16x/16x plus two M.2 SSDs and a high end sound card.
> 
> Which motherboard/cpu combinations would allow me to do the "C)" scenario?



Truly, none.  The GPUs run off the PCI-E lanes provided by the CPU.  The CPU only provides 16 PCI-E lanes.  So you can only do x8/x8.  Some high end motherboard might use a PCI-E bridge chip to give two x16 slots, but the bandwidth back to the CPU is still only a x16, so the benefit is nothing more than a placebo affect and marketing.

If you want to run x16/x16, you have to go to the Socket 2011-V3 X99 platform.


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## Dalkamyr (Jan 16, 2017)

Ok good. So... If wanted to have 2x m.2 SSDs on a z170 motherboard I'd have to make sure the motherboard has TWO pch ports for them? Or would I be forced to use a pci-e slot ? 

Also I read that there are ahci M.2 SSDs and NVME M.2 SSDs. 

I read that some use x2 lanes, others use x4
Google seems to indicate that there are a number of issues with the NVME ones since they're quite new. Apparently some motherboards don't even let you boot windows with them and have read speeds issues... 

Should I wait before getting an nvme?


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## newtekie1 (Jan 16, 2017)

As long as the motherboard has two M.2 slots, you should be fine.  But you can check in the manual to make sure the M.2 slots don't share ports with the graphics slots.

Also, if you are getting M.2 drives, only guy NVMe drives.  There is no point in getting a AHCI M.2 drive unless you just like the form factor, they perform just like SATA drives, and in fact usually use SATA connections on the motherboard instead of PCI-E.


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## Dalkamyr (Jan 16, 2017)

What would be the ideal setup? 

Should I have one M.2 SSD for my windows install and drivers to boot from and ANOTHER m.2 to have my main games on it? 

Or put them all on the same drive. 
If I encounter a system problem where I need to do a clean install, won't it be easier if my windows install is not on the same drive than my documents and games? 

What about the heat issues? 
I hear these m.2 drives need to be cooled???


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## newtekie1 (Jan 16, 2017)

I'd separate things.

Heat shouldn't be an issue.  NVMe drives get warm, but they can't handle it.


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## Dalkamyr (Jan 16, 2017)

https://www.pugetsystems.com/labs/articles/Samsung-950-Pro-M-2-Throttling-Analysis-776/


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## Potatoking (Jan 16, 2017)

most z170 moatherboards have third pciex16 slot connected to chipset so you could use something like this to add 1 pcie SSD and 1 sata m.2 ssd

 
if you want 2X x16 gpu and sound card any x99 board a i-7 6850K or up will work fine.
but running 2 gpus on x8 speed has less than 1% performance hit.

also please dont mix nvme,AHCI with pcie, SATA
sata is interface, AHCI is protocol.

http://www.ebay.com/itm/4X-4-Lane-A...178295?hash=item43ec97c577:g:VjsAAOSwDNdVuFIu


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## Potatoking (Jan 16, 2017)

Dalkamyr said:


> https://www.pugetsystems.com/labs/articles/Samsung-950-Pro-M-2-Throttling-Analysis-776/


new samsung drives have less heat issues (960 pro and evo), but the throttling is minimal, also usually you dont do much ssd writes when GPUs are at 100% load


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## Dalkamyr (Jan 16, 2017)

Potatoking said:


> most z170 moatherboards have third pciex16 slot connected to chipset so you could use something like this to add 1 pcie SSD and 1 sata m.2 ssd
> View attachment 83127
> if you want 2X x16 gpu and sound card any x99 board a i-7 6850K or up will work fine.
> but running 2 gpus on x8 speed has less than 1% performance hit.
> ...



I thought that some m.2 were either achi ou nvme. Ahci being one protocol and nvme the newer protocol no?

Lastly is there a z170 motherboard that allows two m.2 to run at x4 each so they get their full speed without decreasing the gpu to x8?
I'll continue searching on google meanwhile. If I one I'll report back here


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## nomdeplume (Jan 16, 2017)

We need to focus on the simple math here even if it means letting dreams slip away.  20 PCIe lanes = exactly that no matter how much you fudge the equation.  The reality you should focus on is the 6 SATA 3 ports that are on most of the Z170 boards.  Because if you go with one of those x4 NVMe adapter cards that stack on more than two drives that is effectively the speeds you are going to be getting anyways.  

Or move up to X99.  Z270 is probably not a worthwhile ambition just to get 4 more lanes.


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## newtekie1 (Jan 16, 2017)

Dalkamyr said:


> Lastly is there a z170 motherboard that allows two m.2 to run at x4 each so they get their full speed without decreasing the gpu to x8?



Again, almost all of them that have 2 M.2 slots.  The M.2 slots don't use the lanes from the CPU.



nomdeplume said:


> Z270 is probably not a worthwhile ambition just to get 4 more lanes.



Ironically, those 4 extra lanes are there pretty much entirely to allow an extra M.2 slot.


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## alucasa (Jan 16, 2017)

What you need to watch out for is whether M.2 slot occupation reduces your active SATA port number. It should be on mobo manual somehwere. It mainly effect lower end mobo where the lane # gets tight. Top-end, Z-line (Z170, Z270, or even X99) shouldn't suffer from any issues.

Personally, I see the only major benefit of M.2 is reduction of cables. Therefore, I use M.2 as OS drive for all my builds if I am able. I personally see NVMe M.2 as a waste so far in personal PC. For servers, I see its place though in heavy SQL environment.


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## Dalkamyr (Jan 17, 2017)

Yeah sata won't be a problem. The max hdds I see myself having is 2


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## nomdeplume (Jan 17, 2017)

newtekie1 said:


> Ironically, those 4 extra lanes are there pretty much entirely to allow an extra M.2 slot.


Or so it would appear.  Just one of many inconvenient 'oh we could have added that years ago' features Intel is flooding the market with.

Is the sound card for headphones or multichannel speaker setup?


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## newtekie1 (Jan 17, 2017)

Dalkamyr said:


> Yeah sata won't be a problem. The max hdds I see myself having is 2



Except if you use an AHCI M.2 drive, you are using a SATA port.  So many motherboards will share SATA ports, so if you use AHCI on M.2 slot 1, then SATA port 6 becomes deactivated.


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## Dalkamyr (Jan 18, 2017)

Another question. I ordered the Asus maximus hero z270 motherboard. It says in the manual the the mobo has two m.2 ssd ports. Apparently one of them supports the sata/pci-e and the other only the pci-e interface what does this mean?

From my understanding the CPU has 16 pci-e lanes and them z240 have four more than their z170 counterparts. Which means the mobo should have 8x pci-e apart from the 16x the CPU has.

I didn't know m.2 SSDs had different interfaces. Can you advise me on this matter so I don't buy the wrong thing?

Thanks


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## nomdeplume (Jan 18, 2017)

> 2 x M.2 Socket 3 with M Key, type 2242/2260/2280(PCIE 3.0 x4 and SATA modes) and type 2242/2260/2280/22110(support PCIE 3.0 x 4 mode) storage devices support *
> 
> * When the M.2_1 Socket 3 is operating in SATA mode, SATA port 1 will be disabled.
> * When the M.2_2 Socket 3 is operating in PCIEX4 mode, SATA port 5. 6 will be disabled.






newtekie1 said:


> Again, almost all of them that have 2 M.2 slots.  The M.2 slots don't use the lanes from the CPU.






nomdeplume said:


> WZ270 is probably not a worthwhile ambition just to get 4 more lanes.





newtekie1 said:


> Ironically, those 4 extra lanes are there pretty much entirely to allow an extra M.2 slot.


The power of positive reinforcement at work.  What, that is actually what you want?  Getouttahere.

Very quickly

- There are two ways M.2 SSD's connects, SATA and PCIe.
- There are two types of M.2 PCIe SSD, AHCI and NVMe
- Common to all of these there are different length, thickness, and keyed M.2 SSD made for different purposes like netbooks or industrial workstations
- WiFi cards can also use the M.2 slot.  Very common on laptops and mini desktops.

You are going to be looking exclusively at NVMe

Why don't you try watching this overview video of your board.


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## Dalkamyr (Jan 18, 2017)

Well I think I'm starting to understand where my confusion comes from. When I first looked at m.2 drives, I noticed that some literally plugged into a pci-e port on the motherboard the same way a graphics card goes in... Then I noticed the ones that look like ram sticks... 

The ones we are talking about, even though they connect into a special port (not in a traditional pci-e slot) can either run on sata or pci-e (if I got this right) 

*What I thought was that the ones that plug like a graphics card were pci-e and the ones that look like a ram stick were only sata. 
*
Now the other thing, when connected through a sata interface, does the m2 drive perform the same way than through a pci-e interface? 

Is it like max x2 pci-e when in sata Vs x4 in pci-e?

Oh and I went with z270 because I found weekly deal on the Internet, the i7 6700k was the same price as the i7 7700k


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## nomdeplume (Jan 18, 2017)

The x4 PCIe cards for desktops are primarily a way to set up a RAID array or just add more SSD than your have SATA ports.  What you appear to have missed is you install M.2 SSD onto them or buy a prebuilt with them installed under a heatsink.  Very few new M.2 are made that run on AHCI as opposed NVMe.  With your MB and BIOS just buy an NVME in the correct key and you'll be fine. 

Installing the drive into a header on your mb means losing either SATA1 or both 5 & 6.  If you choose the SATA interface the main difference is SATA speeds and only losing one SATA port.  

So if you install and run a NVMe SSD in the M.2 port that leaves your PCIe slots free to divy them up between video cards however you wish.


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## Dalkamyr (Jan 18, 2017)

I'm thinking about getting the samsung pro 960 or 950 SSDs.
I'm also considering getting a pci-e adapter with a heatsink to prevent heat throttling.

would that work on my motherboard or must I absolutely use the provided m.2 ports?


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