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Started by luisquiles | | 3 answers
Help me with M.2 PCI-e 2x
I'm looking for a M.2 storage solution. I got a MSI Z97 Gaming 7. I got a graphic card installed. What if i install the M.2 based on PCI-e 2x? Is going to downgrade my card's lanes to 8x so it can fit the 16x lanes of the CPU?

Full specs:

Intel Core i5 4570
MSI Z97 Gaming 7
8GB DDR3 (OC)2400Mghz
240GB SSD Mushkin
ASUS R9 270X 2GB DirectCU II TOP OC
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a b U Graphics card
a b à CPUs
a b V Motherboard
October 8, 2014 11:40:39 PM

luisquiles said:
NiCoM said:
Pretty sure you'll need to use the M.2 SSD slot, not just any pci-e express port.

Running it in PCI-e 3.0 x2 shouldn't be a problem, but some mobos might downgrade it to PCI-e 2.0 x2 if you have multiple gpus, which is going to be a problem if you go for a faster M.2 SSD. Here's the list of speeds:

M.2 PCIE (2.0x2) 1000 MB/s (8Gb/s)
M.2 PCIE (2.0x4) 2000 MB/s (16Gb/s)
M.2 PCIE (3.0X2) 2000 MB/s (16Gb/s)
M.2 PCIE (3.0X4) Ultra 4000 MB/s (32Gb/s)

So if it's PCI-e 2.0 x2 then you'll have no problems up to 2000mb/s speeds, though SOME mobos will kick the speed down to PCI-e 2.0 x2 when you add more gpus.

Even if it downgraded your GPU lane, then it wouldn't matter, since you could run PCI-e 2.0 x16 with no performance difference. But you should really try to look for M.2 in your manual to see if it says anything about it, if you can't find a answer and are dying to know, then go to MSI support to find out ;) 


I find out that my M.2 port is based on PCI-e Gen2 x2. If I install a SSD based on PCI-e, can this makes my graphics card slower?




If you only have one gpu then it's probably running PCI-e 3.0 x16, your gpu won't be bottlenecked if it's running something slower, I'm also pretty sure it most of the time only goes the other way, that you'll have a lower speed on the M.2, though with PCI-e 2.0 x2 im pretty sure it won't touch any other PCI-e lanes having it installed. The newer X99 boards have faster M.2, and they will downgrade the M.2 if they have too many gpus installed.

So i think you'll have full speed on both PCI-e for your gpu and M.2, remember you're limited to 1000mb/s, there's no reason to buy anything faster than that.

AND even if the SSD halved the gpus PCI-e lane, it would still run at 99,9% of it's performance.
October 8, 2014 11:05:44 AM

NiCoM said:
Pretty sure you'll need to use the M.2 SSD slot, not just any pci-e express port.

Running it in PCI-e 3.0 x2 shouldn't be a problem, but some mobos might downgrade it to PCI-e 2.0 x2 if you have multiple gpus, which is going to be a problem if you go for a faster M.2 SSD. Here's the list of speeds:

M.2 PCIE (2.0x2) 1000 MB/s (8Gb/s)
M.2 PCIE (2.0x4) 2000 MB/s (16Gb/s)
M.2 PCIE (3.0X2) 2000 MB/s (16Gb/s)
M.2 PCIE (3.0X4) Ultra 4000 MB/s (32Gb/s)

So if it's PCI-e 2.0 x2 then you'll have no problems up to 2000mb/s speeds, though SOME mobos will kick the speed down to PCI-e 2.0 x2 when you add more gpus.

Even if it downgraded your GPU lane, then it wouldn't matter, since you could run PCI-e 2.0 x16 with no performance difference. But you should really try to look for M.2 in your manual to see if it says anything about it, if you can't find a answer and are dying to know, then go to MSI support to find out ;) 


I find out that my M.2 port is based on PCI-e Gen2 x2. If I install a SSD based on PCI-e, can this makes my graphics card slower?


Best solution chosen by luisquiles

a b U Graphics card
a b à CPUs
a b V Motherboard
October 8, 2014 9:40:11 AM

Pretty sure you'll need to use the M.2 SSD slot, not just any pci-e express port.

Running it in PCI-e 3.0 x2 shouldn't be a problem, but some mobos might downgrade it to PCI-e 2.0 x2 if you have multiple gpus, which is going to be a problem if you go for a faster M.2 SSD. Here's the list of speeds:

M.2 PCIE (2.0x2) 1000 MB/s (8Gb/s)
M.2 PCIE (2.0x4) 2000 MB/s (16Gb/s)
M.2 PCIE (3.0X2) 2000 MB/s (16Gb/s)
M.2 PCIE (3.0X4) Ultra 4000 MB/s (32Gb/s)

So if it's PCI-e 2.0 x2 then you'll have no problems up to 2000mb/s speeds, though SOME mobos will kick the speed down to PCI-e 2.0 x2 when you add more gpus.

Even if it downgraded your GPU lane, then it wouldn't matter, since you could run PCI-e 2.0 x16 with no performance difference. But you should really try to look for M.2 in your manual to see if it says anything about it, if you can't find a answer and are dying to know, then go to MSI support to find out ;) 

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