SSD Speeds on 5.1

[mastermamo]

Hi guys

I have a general question which perhaps a few of u can shed some light on.
I have a few Mac Pros but on my 2012 12 core I use 3 SSD's.
! x Samsung EVO 850 (Boot Drive)
1 x Samsung Evo 840 (CCC Backup Drive)
1 x OWC Mercury Electra 6G (Scratch Drive)

The max speeds on these are 6Gb/s. I know the Macs support SATA 2 and not 3 but is there a workaround to achieve max speeds?
Is there any possible way to reach the 6Gb/s speeds these drives are capable off or will I need to go the flash based Pci-e drive route?
[doublepost=1484586342][/doublepost]Oh dear ok I just saw this post which answers my question

https://forums.macrumors.com/threads/ssd-in-mp-5-1-not-expected-results.1974827/

 

[AndreeOnline]

In a single bay you'll hit the ceiling, real life, at around 220 to 235 MB/s write and 260 MB/s read.

If you RAID 0 two over two bays you get closer to the drives capacity at double those numbers.

Remember that all those fancy read/write speeds you see is with larger files. Day to day, while there is a difference between Sata 3Gbps and PCIe, the difference might be smaller than you think in many situations with smaller read/writes. To me personally, SSDs are primarily about the fast access times.

 

[mastermamo]

Can u Raid if you are using 2 SSD's in the DVD Rom SATA ports?

 

[h9826790]

Can u Raid if you are using 2 SSD's in the DVD Rom SATA ports?

Yes

 

[flowrider]

If you have the slots, I would, and did, go with PCIe cards.

I have an Angelbird with an SM951 and an Apricorn Velocity Duo with Samsung SSDs (1 840 Pro and 1 840 EVO). Speeds are attached. The first is the SM951, The second the Pro on the Card, the third an EVO in a drive bay.

Lou

 

[macuser453787]

The max speeds on these are 6Gb/s. I know the Macs support SATA 2 and not 3 but is there a workaround to achieve max speeds?

There is a hardware-based solution that works very well. Check out this product from Max Upgrades. This kit includes drive sleds with a custom connector that uses the Mac Pro's backplane for POWER only, NOT for DATA.

It requires using a controller card with mini-SAS connectivity (such as a RAID controller), but using this kit you can achieve proper SATA 3 speeds with your single drives. Another benefit of this option is that if you choose to use RAID, using a RAID controller card takes the RAID calculations away from the CPU, which frees up the CPU to work on other tasks. (This is in contrast to using a software-based RAID setup, which relies on the CPU for its calculations.)

I have this setup in my cMP 4,1(5,1) hooked up to an Areca controller with 4 Samsung 840 Pros in a RAID stripe and AJA benchmarks it at about 1900 MB/s.

The flip side of this setup is of course the price of the kit and the controller card.

 

[mastermamo]

Thanks will have a look at this option

 

[AlanKeaveney]

If you have the slots, I would, and did, go with PCIe cards.

I have an Angelbird with an SM951 and an Apricorn Velocity Duo with Samsung SSDs (1 840 Pro and 1 840 EVO). Speeds are attached. The first is the SM951, The second the Pro on the Card, the third an EVO in a drive bay.

Lou

View attachment 683989 View attachment 683990 View attachment 683991

Hi Flowrider,
Ive been trying to find out what would the bottleneck be in my 2009 4,1->5,1 MP for a m.2 SSD upgrade.
Have you that Angelbird in a PCI-E 2 x16 slot?

Below is the max speeds I saw on site on PCI-Express:


Summary of PCI Express Interface Parameters:

• Base Clock Speed: PCIe 3.0 = 8.0GHz, PCIe 2.0 = 5.0GHz, PCIe 1.1 = 2.5GHz
• Data Rate: PCIe 3.0 = 1000MB/s, PCIe 2.0 = 500MB/s, PCIe 1.1 = 250MB/s
• Total Bandwidth: (x16 link): PCIe 3.0 = 32GB/s, PCIe 2.0 = 16GB/s, PCIe 1.1 = 8GB/s
• Data Transfer Rate: PCIe 3.0 = 8.0GT/s, PCIe 2.0= 5.0GT/s, PCIe 1.1 = 2.5GT/s
  
  

 

[flowrider]

^^^^My Angelbird is in PCIe slot 3, a 4X slot. The Apricorn is in slot 2. IIRC there are problems with the SM951 associated with being mounted in slot 2.

Lou

 

[macuser453787]

Ive been trying to find out what would the bottleneck be in my 2009 4,1->5,1 MP for a m.2 SSD upgrade.
Have you that Angelbird in a PCI-E 2 x16 slot?

I have the Angelbird as well (with an SM951 mounted on it), and I believe the x4 slot is the appropriate slot for that card because the card itself is x4 and putting it in an x16 slot won't yield higher speeds.

 

[Motoman69]

Will the Angelbird work with the new Samsung 860 EVO NVME? . I just got one for a PC and have a cheap PCIE card. I also have a Apricorn Velocity Duo with std Samsung 850 EVO, Did you have to update the MacOS with any Kext files for the Angelbird SM951 combo?

 

[PowerMike G5]

^^^^My Angelbird is in PCIe slot 3, a 4X slot. The Apricorn is in slot 2. IIRC there are problems with the SM951 associated with being mounted in slot 2.

Lou

Yes, I had issues with the SM951 in the x16 slot 2 using the Lycom DT-120. The only solution that seems to work In the x16 slot 2 is the Amfeltec card. It divides the slot into four x4 slots on the card and runs each one at full speed. I have it with an SM951 in each slot and I achieve the 1400MB/s-1500MB/s average on each one.

 

[Squuiid]

Will the Angelbird work with the new Samsung 860 EVO NVME? . I just got one for a PC and have a cheap PCIE card. I also have a Apricorn Velocity Duo with std Samsung 850 EVO, Did you have to update the MacOS with any Kext files for the Angelbird SM951 combo?

NVME won't work in a Mac Pro. There are hacky drivers for it but not worth the trouble IMO, and it wouldn't be bootable.
No drivers are required for the SM951/Angelbird/Lycom combos.
However, the SM951 and XP941 drives are hard to find. Your best bet is the following:
HyperX Predator PCIe 480GB AHCI SSD (The only compatible PCIe SSD for the Mac Pro that's still readily available)
https://www.amazon.com/gp/product/B00V01C6M8/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER