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Samsung 970 EVO M.2 NVMe SSD

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Thought I'd share some feedback regarding my results. Having swapped the Samsung 970 EVO Plus for the 970 Pro, macOS Mojave installs and runs without error.

It is a pity that the Plus cannot be used with macOS, since it costs significantly less than the Pro and is capable of much higher write speeds.

I've attached screenshots of disk speed tests using both drives in Windows, where the Plus functioned well. Also attached are screenshots of disk speed tests in Mojave, where the performance degradation of the Plus is clearly reflected.

Even though more expensive and unnecessary for consumer workstation use, it is worth noting that the Pro does have the 2-bit MLC advantage.

Very helpful information. Thnx for sharing. Just found out about the EVO Plus limitations although am still not sure what the anomaly could be that results in the performance hit. :problem:
 
I need a little help here
Mojave 10.14.4, Clover 4910
970 EVO 500GB
PCI adapter in 2nd PCIe x4 slot (first is a graphic) Jeyi Coolswift
Z77-DS3H modded bios (added NVMe dxe module for boot)

Everything is fine, fast boot etc, but I don't get full speeds, looks like PCIx2, but most weird is 4K test as you can see on screenshot. Any ideas what's wrong here ?

UPDATE: Tried with original BIOS booting from SATA clover - nothing changes, added second partition HFS+ to eliminate APFS - nothing changes

Should I try with different adapter ? Is there any clover setting that can cause that or Clover driver ?
 

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I need a little help here
Mojave 10.14.4, Clover 4910
970 Evo 500GB
Pci adapter in 2nd slot x4 (first is a graphic) Jeyi Coolswift
Z77-DS3H modded bios (added NVMe dxe module for boot)

Everything is fine, fast boot etc, but I don't get full speeds, looks like Pcix2, but most weird is 4K test as you can see on screenshot. Any ideas what's wrong here ?

UPDATE: Tried with original BIOS booting from Sata clover - nothing changes, added second partition HFS+ to eliminate APFS - nothing changes

Should I try with different adapter ? Is there any clover setting that can cause that or clover driver ?

Looks like you are hitting the limits of PCI-e 2.0. MacPro1,1-5,1 users have the same issue.
 
Looks like you are hitting the limits of PCI-e 2.0. MacPro1,1-5,1 users have the same issue.

Isn't the blue ports on this board PCI-e 3.0? And this 4k write at 30 mb/s isn't close to limits right ?
 
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Isn't the blue ports on this board PCI-e 3.0? And this 4k write at 30 mb/s isn't close to limits right ?

2.0 and 3.0 have the same size socket but the 2.0 runs at 8 lanes versus 16 with 3.0.
 
2.0 and 3.0 have the same size socket but the 2.0 runs at 8 lanes versus 16 with 3.0.

yea I know, I was referring to my specific motherboard Z77-DS3H, am I wrong ?

Also I run a test on Win 10, writing speeds at 4k looks ok there, so I'm assuming this AmorphousDiskMark is unreliable (even on osx when you run test on exFAT). But the cap 1,5Gb/s is still there and I wonder where is the bottleneck. Read a lot of stories about newer motherboards with same problem and the only thing to come is BIOS :/
 

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I know running my 970 EVO on my Z97 I get similar speeds, jump to the Z170 and it doubles. The bios and the board capability. My Z97 has NVMe slot but it’s limited to 10Gb/sec so it’s actually slower than using with a PCI adapter.
So it’s probably a combination of BIOS and board capability/speed. These drives weren’t available or at least not practical when the older boards were made.
 
I removed graphic card from slot x16, leaving M.2 in x4 - nothing changed, put M.2 adapter in x16 and BOOM full speed. I believe this adapter only using x4, so my call is that BIOS is glitched on that 2nd slot and only option is to flash it with modded or different mb BIOS. :/
 

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I removed graphic card from slot x16, leaving M.2 in x4 - nothing changed, put M.2 adapter in x16 and BOOM full speed. I believe this adapter only using x4, so my call is that BIOS is glitched on that 2nd slot and only option is to flash it with modded or different mb BIOS. :/

The available lanes greatly decrease when using a graphics card. That slot is first on the list so when a graphics cards is inserted the leftover lanes/slots are reduced. You may check into BIOS features to see if you can adjust things as well. Sometimes there is the PCI setting for automatic versus Gen1, Gen2, Gen3 etc...
 
The available lanes greatly decrease when using a graphics card. That slot is first on the list so when a graphics cards is inserted the leftover lanes/slots are reduced. You may check into BIOS features to see if you can adjust things as well. Sometimes there is the PCI setting for automatic versus Gen1, Gen2, Gen3 etc...

There is only PEG option, and I already set it to Gen3. All other slots are empty, BTW. So 4 lanes should be there. I will ask Gigabyte to be sure how it works.
 
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