GA Z97-D3H (m.2 pcie ssd lanes )

[migf1]

Hello,

I've recentlly purchased a GA Z97-D3H (rev 1.1) mobo. In its m.2 pcie ssd compatibility list, it includes the Samsung XP941 pcie ssd, stating 4 lanes under the "PCie Bus" column (that ssd comes with a 4-lanes capable PCIe 2.0 m.2 controller).

Does this mean that the m.2 slot of this mobo can provide 4 pcie-lanes? I read on the Internet that the Z97/H97 chipsets provide 2 pcie 2.0 lanes per sata-express slot, and this board has only one sate-express slot. It is my understanding that the m.2 and the sata-express of this board use the same PCIe 2.0 interface (probably that's why they are mutually exclusive).

So, should I go for a PCIe 2.0 4-lanes m.2 pcie ssd disk, or save some bucks and get a 2-lanes m.2 pcie ssd disk?

Thanks in advance.

PS. On a related note, I assume that purchasing a pure PCIe x4 ssd disk (non m.2) and plugging it directly onto the PCIe x4 of this board, would use all 4 lanes, right?

[dmdilks]

It really doesn't have anything to do with your PCie slots. It is part of the Sata ports.

On the motherboard there are three length adjustment holes for the M.2 SSD. Select the proper
hole for the M.2 SSD to be installed and re-fasten the screw and nut.

M.2, SATA Express, and SATA3 4/5 connectors can only be used one at a time. The SATA3 4/5
connectors will become unavailable when an M.2 SSD is installed.

[migf1]

Thank you for the rapid response!

However, I am a bit confused. Do you mean that this board cannot use a m.2 pcie ssd at all (only a m.2 sata3 ssd)?

In the Overview section of the mobo's site, under "M.2 Onboard Connector" it says:

GIGABYTE 9 series motherboards come equipped with an onboard M.2 slot, providing users PCI-Express connectivity for SSD devices. Delivering up to 10 Gb/s data transfer speeds, M.2 offers users considerably faster storage performance than current mSATA and even SATA Revision 3 (6Gb/s) storage devices.

Since sata-express is supposed (by the standard) to support both sata3 and pcie, and since the m.2 of this board is mutually exclusive with tha sata-express, I assumed that they both use the pcie bus (regardless of the other explicit PCIe slots of the board).

The m.2 ssd compatibility list of this mobo, makes a clear distinction between m.2 sata disks, and m.2 pcie ssd's, meaning (as I undertsand it) that the board is capable of accessing the pcie bus throuhg its m.2 connector (this will diasble access to the sata-express and 2 sata3 ports, but for this particular case I don't really care).

if I'm not way off and the above actually holds, then does the m.2 slot utilize 2 or 4 pcie lanes?

Thanks.

[dmdilks]

It is all new to me too but here are some reviews on it.

http://www.tweaktown.com/reviews/6372/samsung-xp941-512gb-m-2-pcie-ssd-review/index.html

http://www.beyondwindows9.com/index.php/topic/13834-samsung-xp941-512gb-m2-pcie-ssd-review/

[migf1]

I had already found those linked articles, along with sevral others, but I wanted to make sure. Thanks for trying to help me here, though.

I guess my best bet is to ask directly the Gigabyte tech support (unless someone else jumps in to this thread with more info).

Thanks again.

[dmdilks]

I'm sorry I couldn't help, but I was looking at the one of the drives myself. After you put this thread up. I'm thinking on buying the 128gb and try it as OS drive.

For a drive that has been out there for over a year there isn't too much on it is there. On how many lanes it will use and if will take anything away from video card. If I get one I'll put it in the M2 slot on my X99 board.

[migf1]

I've only recently started digging up to this stuff, and mostly for the Z97 chipset, so I'm not sure what's the deal with m.2 and the X99 chipset.

According to articles such this one, on Tweaktown, most Χ99 boards provide 4 pcie lanes through each one of their m.2 connectors. However I don't know if they are gen-2 or gen-3 PCIe lanes (I think it depends on the mobo).

It also says that making such a m.2 pcie ssd the boot disk, is no issue with the X99 chipset (for Z97 that was not always true, because for OEM drives such as the XP941 ssd which is lacking legacy support in its firmware, special care must be taken by the mobo's bios... I don't know if this has been fixed in the latest bios's, but for some Z97 Gigabyte boards, some guys patched the bios by themshelves with the Sasmung DXE driver, extracting it fisrt from the bios of the AsRock Z97 Extreme 6).

Samsung has already announced the SM951 ssd with an m.2 PCIe gen-3 x4 controller (ditching ACHI in favor of NVMe).

I think this guy sums things up nicely enough.

Also, it is my understanding that generally, it is considered better to go for large size ssd's, because they have more NAND cells to work with in parallel.

I guess it would be wise to check what of the above specs your mobo supports, before purchasing the ssd (and perhaps before trying to set it up as a boot disk).

[autotech]

For the fastest you would want 4 lanes. The M2 connector on this board has a dedicated 4 lane pci path to the chipset. You can populate it 3 different ways. 1 is just a sata express connector 2 is 2 x sata drives or 3 a M2 drive. You can not use a pci express and a m2 drive at the same time. You also can not use 2 sata drives and a m2 at the same time.

This will not take bandwidth away from the video card at all as that is on a separate pciE path.

[migf1]

For the fastest you would want 4 lanes. The M2 connector on this board has a dedicated 4 lane pci path to the chipset. You can populate it 3 different ways. 1 is just a sata express connector 2 is 2 x sata drives or 3 a M2 drive. You can not use a pci express and a m2 drive at the same time. You also can not use 2 sata drives and a m2 at the same time.

This will not take bandwidth away from the video card at all as that is on a separate pciE path.

Thank you so much!

So the m.2 connector of this board does indeed provide 4 PCIe 2.0 lanes! This certainly makes my day, thanks again

Still a bit confused though about the "you cannot" parts. I know from the docs that the m.2, sata-express and 2 of the sata3 slots (the ones provided by the sata-express) are mutually exclusive.

If I get you right, your are saying that we cannot populate both the m.2 and the explicit PCIe 2.0 x4 slot of this board at the same time, too?

Also, when you say we cannot have an m.2 and 2 sata drives at the same time, you mean any 2 sata3 slots, or those 2 already mentioned in the docs (there's a total of 6 sata3 slots on the mobo, with 2 of them provided via the sata-express interface).

Thanks in advance.

[autotech]

Where your m2 is, also on that lane is a sata express slot. So you can not populate both at the same time. Sata express slot consist of 2 x sata 6 gig ports with the express connector so it makes it a sata express. So if you use the m2 slot it will disable the sata express on that lane.

That still leaves you all your sata 3.0 slots you can use which are the 4 on the sata lane. The pcie x 4 slot is separate so you can use it. It will not affect the m2 lane.

[migf1]

Thank you for the clarification!
This is certainly good news

[sgtsixpack]

Taken from page 105 of 9-series-chipset-pch-datasheet.pdf

I looked at reviews and it said that there are only 2 pci-e lanes used for the m.2 slot.  This data sheet seems to confirm that.  Says 18 high speed i/o where some can be multiplexed (I would not have used that word myself) or configured for pci-e/usb or pci-e/sata port.  I did not see any reference to graphics card pci-e lanes.