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MP 1,1-5,1 Fastest M.2 SSD (Mac Pro 5,1)
- Thread starter rabidz7
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PCIe SSDs - NVMe & AHCI
This is a general info thread for blade SSDs that can be used in the Mac Pro. This is a WikiPost so anyone with the proper credentials may edit it. NVMe SSDs can be used as a boot drive in the MP5,1 and MP6,1 with the latest firmware installed (beginning with version 140.0.0.0.0 for MP5,1 and...
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If you use a Sonnet 4x4 or similar x16 PCIe switch card that takes NVMe SSD's, it'll top out ~6000MByte/s...so a 3-member RAID-0 array will saturate the x16 slot.
Certainly a single NVMe SSD on the PCIe card will be seen independently and be bootable. I haven't thought through the possibility/impossibility of a software RAID-0 as a bootable configuration ... others on this forum can offer guidance there. But the main thing that keeps me from even considering it is that the change from a regular SATA SSD to an NVMe SSD doesn't offer a large/satisfying improvement in boot time.
Even if there are tweaks to make the Raid'ed NVMes bootable it makes no big sense, with every system update you risk a system brick.
Better put your scrap and work files on a raid and let the OS on a Single NVMe.
2nd pro is the ability to set it in a simple PCI Adapter to keep it working if the PCI Card with switch fails.
Better put your scrap and work files on a raid and let the OS on a Single NVMe.
2nd pro is the ability to set it in a simple PCI Adapter to keep it working if the PCI Card with switch fails.
The Sonnet card is the best of those types for the Mac Pro 5,1 - I have one. And I moved it into my 7,1 to run Windows on NVME.
I'd suggest just using a normal SSD for the OS and the NVME for working files. On the 5,1 the system didn't start appreciably faster than with a normal SSD, however once started and in MacOS everything was really quick.
Booting from Raid is not worth the trouble.
I'd suggest just using a normal SSD for the OS and the NVME for working files. On the 5,1 the system didn't start appreciably faster than with a normal SSD, however once started and in MacOS everything was really quick.
Booting from Raid is not worth the trouble.
For the OP.. the answer to your question is the Samsung 970 Pro PCIe SSD [NVME] or the Apple Samsung SSUBX PCIe SSD [AHCI]
These are the last of the 2-bit MLC NAND m.2 PCIe SSDs. If cooled correctly.. neither will ever throttle.
Every other m.2 PCIe SSD ever released will throttle down to around 30% of it's advertised maximum speed as soon as the disk controller cache maxes out. As a loose guide, this 70% drop in data transfer speed usually kicks in after the first 40GB is transferred (just abysmal).
PS: I boot from RAID [HFS+] but i'm running 10.13. Booting from Raid is DEFINITELY not worth the trouble once you start working with APFS.
These are the last of the 2-bit MLC NAND m.2 PCIe SSDs. If cooled correctly.. neither will ever throttle.
Every other m.2 PCIe SSD ever released will throttle down to around 30% of it's advertised maximum speed as soon as the disk controller cache maxes out. As a loose guide, this 70% drop in data transfer speed usually kicks in after the first 40GB is transferred (just abysmal).
PS: I boot from RAID [HFS+] but i'm running 10.13. Booting from Raid is DEFINITELY not worth the trouble once you start working with APFS.
2-member. 3500 MBytes/s read speed is a common ceiling for non-specialist NVMe blades.
Is it "the best" because you have one or is there any specific reason it is "the best"? Highpoint SSD7101A-1 is widely considered a non plus ultra in regards of NVMe controller cards and retails about the same as the Sonnet M.2 4x4 Silent. Then almost every card with ASMedia ASM2824 PCIe Switch (Syba SI-PEX40129 for example) is bootable in 4,1/5,1 and exploits their PCIe bandwidth to the maximum while being about 3 times cheaper then the Sonnet or Highpoint (albeit with two blades maximum). I used Sonnet hardware years ago, but don't know what makes them so special.
I'd personally say, the best bang for buck right now for a 4,1/5,1 owner would be the Sonnet McFiver (if no more than two blades are needed). Lots of added value for the price of a 4-blade controller.
I may not know the technology well enough, but why would cooling down a SSD help with oversaturating the cache?
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The 2-bit NAND cells write directly (no caching) but they're expensive to manufacture compared with 3-bit NAND flash storage options. Eventually, the poor 'sustained write speeds' of 3-bit NAND were masked by some clever logic in the NVMe SSD controllers [e.g. Samsung calls it "Intelligent Turbowrite"].
The only reason you couldn't realise promised speeds in the 2-bit NAND era was overheating (no cache to oversaturate).
The only reason you couldn't realise promised speeds in the 2-bit NAND era was overheating (no cache to oversaturate).
OK, that’s what I didn’t know, the differences between various NAND approaches and masking the cheaper tech with massive caches, thanks for that.