# M.2 vs PCIe lanes



## Tibor Hazafi (Jul 20, 2016)

Hi all,
I would like to buy an MSI H97 Gaming 3 MoBo with i7-4790K, which supports maximum 16 PCIe lanes. My question is: If I have a discrete VGA (16 lane (Gen3 x16) and an M.2 PCIe SSD (2 lane (Gen2 x2), then wouldn't be a problem that it's more than the maximum supported 16?
Thanks,
hazazs


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## puma99dk| (Jul 20, 2016)

MSI writes this: * The SATA5 and SATA6 ports will be unavailable when installing a module in the M.2 port.

Link: https://www.msi.com/Motherboard/H97-GAMING-3.html#hero-specification

So ur GFX will run full pci-e x16 when u insert a m.2. drive in ur board but sata connector 5&6 will be disabled.


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## newtekie1 (Jul 20, 2016)

The H97 chipset provides 8 extra PCI-E 2.0 lanes.  The M.2 slot uses some of these extra lanes, not the lanes from the CPU.


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## Ebo (Jul 20, 2016)

to keep it simple, 1 GFX 16 pci-e lanes, 1 M2 4 lanes which means you at least need 20 lanes. Your CPU and chipset dosent support it just execpt you have a PLX-chip on it.


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## newtekie1 (Jul 20, 2016)

Ebo said:


> to keep it simple, 1 GFX 16 pci-e lanes, 1 M2 4 lanes which means you at least need 20 lanes. Your CPU and chipset dosent support it just execpt you have a PLX-chip on it.



His CPU and chipset support it just fine.  The CPU and chipset provide a total of 24 PCI-E lanes.  Also, the M.2 slot only use 2 PCI-E lanes.


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## little cat (Jul 20, 2016)

https://www.pugetsystems.com/labs/articles/Z97-vs-H97---What-is-the-Difference-562/


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## basco (Jul 21, 2016)

if you really want to go the m2 ssd way i would strongly recommend a mainboard with m2 port PCIe Gen2 x4 slot.
if not you are limited to max 800mb\s and then i dont see the profit to normal sata ssd and price is higher too.

i tried to find mainboards with z\h97 with PCIe 2.0 x4 
but there are only 2 with PCIe3.0x4 all others are 2.0x2 ??


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## little cat (Jul 21, 2016)

The lanes for M2 ssd should come from the chipset . 
I would get a standard ssd


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## newtekie1 (Jul 21, 2016)

basco said:


> if you really want to go the m2 ssd way i would strongly recommend a mainboard with m2 port PCIe Gen2 x4 slot.
> if not you are limited to max 800mb\s and then i dont see the profit to normal sata ssd and price is higher too.
> 
> i tried to find mainboards with z\h97 with PCIe 2.0 x4
> but there are only 2 with PCIe3.0x4 all others are 2.0x2 ??



The raw throughput isn't really what helps M.2 drives, it is NVME, which removes the bottleneck when trying to do multiple reads/writes at the same time.


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