Install SSD Drive Bay SATA vs Optical SATA , va OWC OWC Accelsior S?

macjunkie2013

macrumors member
Original poster
Jun 9, 2013
43
47
You Ess Eh
My Mac Pro is mid 2010 5.1 in Sierra 10.12.6, and will be updating to Mojave pretty soon so I can run a Sapphire Vega 64. I currently run a RX 580 via Pixlas mod. I already have Dual Xeon X5690's and 65gb ram.

Currently I have a Boot drive as a WD Blue 1TB mounted on a PCIe x4 OWC Accelsior S. It has been working great, so I hope there will no issues upgrading to Mojave. I have been holding off as I heard that Mojave might be slower than Sierra in some cases

After reading several posts here on SSDs, I am wondering if moving the SSD to the SATA drive or optical bay would result in a significant performance drop? I do have one free drive bay still.

What I understand is, that the OWC Accelsior S is faster than SATA but not by much and may only be noticeable on +1GB files? Seems like a wasted PCIe slot as to see any real usable/significant performance gain I would need to use a Highpoint 7101A w Samsung 970 PRO NVMe?

I mostly use my Mac for 3D Maya, Modo, zBrush, Photoshop and Substance Painter, so the biggest files are simply images and PSDs or textures. For video editing I use HitFilm, but only rarely.


I would be grateful for advice or user experience, Happy Turkey Day!
 

Slash-2CPU

macrumors 6502
Dec 14, 2016
299
156
New Orleans, USA
If you need the PCIe slot for another purpose, you won’t lose that much speed moving the SSD to onboard SATA.

If you don’t need the PCIe slot, I would leave it on the slot.

If you have other SSD drives on the onboard SATA, be aware that the total available throughput on the link back to the northbridge is 630-700 MB/s. You’ll hit that pretty easily if moving large files on SSD RAID.

Additionally, PCIe slots 3 and 4 share the same x4 link(1500-1550MB/s) to the northbridge.

My current setup:
Dual M.2 drives in slot 2.
USB 3.1 Gen2 card in slot 3
Sonnet Tempo Pro SATA card in slot 4.

Tempo Pro is hosting two 2TB SSD’s
I have another two 2TB SSD’s in onboard bays 1 and 2.(limited by SATA300 to about 266MB/s each)
All 4 drives are in a RAID 0 that gives me 1000-1100MB/s read and write with awesome random IO performance as well.
One way around the onboard SATA total bandwidth limit.
 
Last edited:

macjunkie2013

macrumors member
Original poster
Jun 9, 2013
43
47
You Ess Eh
Hey Slash-2CPU

Thanks for responding.

If I correctly understand your setup

Slot 1 RX 580
Slot 2 Dual M.2 (boot drive w 2x 960 PRO NVMe?)
Slot 3 USB 3 Card
Slot 4 You have a 8TB Raid 0 by combining 2 SSDs from Tempo Pro, with 2 SSDs each in a drive bay. That combined gets you ~1100MB/s RW a bit over the individual the SATA (x2) ~532 MB/s limit or Sonnett Pro ~850 MB/s(maybe less.?) and well over the combined SATA limit of 700 MB/s. Pretty cool idea.

I assume your System and Apps are on M.2, and the 8TB Raid is your media drive?

My current MacPro setup is:

Slot 1 RX 580
Slot 2 OPEN
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S

I hoping to add a flashed MSI R9 280x to slot 2, but that would cover my Slot 3, and I need the USB 3 card, that leads me to thinking I may not need the OWC card.

With a single SSD might be showing its age and that at best I might be getting ~545 MB/s, or roughly double what 1x SATA would do. Thanks for the info on the max SATA speed of ~700 MB/s, so to switching to RAID 0 with 3 SSD's in 3 SATA bays might best me comparable performance without using the PCIe slot? Would a SSD Raid 0 in 3x SATA drives, be bootable?

Alternatively replacing the OWC card with a Lycom DT-120 + 1TB Samsung 960 EVO (+140.0.0.0.0 firemare) might get me more noticeable app launch, and UI speed.
I know that boot time may not improve.

Ultimately the most economical path for the maximum performance gain is the leave the 280X out, and replace the OWC with Lycom/Samsung combo?

Cheers and Happy Turkey Day.
 
Last edited:

Slash-2CPU

macrumors 6502
Dec 14, 2016
299
156
New Orleans, USA
Slot 2 is the I/o Crest SI_PEX40129. Dual M.2 to PCIe x8. On there I have a 960 Pro boot and SM951 scratch. It's basically one half of a 7101A at half the price. ~3000MB/s.

The Sonnet Tempo SATA maxed out ~950MB/s for 2-drive RAID 0 sequential(not sure if it was drive or interface limit). I needed high random I/O numbers and 8TB total capacity, so 4x2TB in a split configuration made sense. Only other way to get 8TB on SATA would've been all 4 drives on internal sleds, with a performance penalty for sequential performance or 2x4TB on the Sonnet card for way more $ and a massive random IOPS penalty.

10.13 and later does not support booting from any RAID.

There's a few ways to do this, depending on what you're trying to accomplish. With BootROM 140.0.0.0.0, Slot 2 will now link up at PCIe 2.0(5gbps) speeds for NVMe drives.

You don't want your NVMe drive on slot 3 or 4 since any activity on the other slot will rob bandwidth from the NVMe drive. Slots 3 and 4 share the same x4 link. Accelsior plus USB3 doesn't add up to 1500MB/s, so they will play nice together on a x4 link.

Best bang for the buck:
Slot 1 RX 580
Slot 2 Lycom+Samsung NVMe
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S

Max performance:
Slot 1 RX 580
Slot 2 SI_PEX40129+ 1 or 2 Samsung NVMe
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S

If you want boot screens, the port arrangement on the R9 280 I had was basically single-slot. You could creatively mount it into slot 4 while losing the space of drive bays 3 and 4. Would require removing the R9 280's bracket, chopping off the 2nd slot area of the bracket, and reinstalling the bracket. Good news is the bracket is a cheaply replaceable part. Buying a dead R9 280 from eBay and chopping up that donor card's bracket would be wise. Powering both the 280 and a 580 would require an additional mod that's commonly discussed on this forum.

The I Want It All option:
Max performance:
Slot 1 RX 580
Slot 2 SI_PEX40129+ 1 or 2 Samsung NVMe
Slot 3 USB 3 Card
Slot 4 Modded R9 280 also obstructing bays 3 and 4.
SATA SSD in optical bay or bay 1/2.
 

macjunkie2013

macrumors member
Original poster
Jun 9, 2013
43
47
You Ess Eh
Hey Slash-2CPU, several great suggestions.

My mac has the Pixlas mod so I think powering both cards (280 + Vega 64 eventually) should be fine? Did not think of moving the 280x to slot 4, that might work..

So to be clear you are using two SSD's in the SI_PEX40129, they are not RAID just simply boot + scratch, clever! I might just get the SI_PEX40129 and add one SSD for now. Hmmm....

In regards to your RAID, the combined drives give you fast random I/O because part of it is SATA?

Thank you for your time and effort, gives me something to think about as I recover from eating turkey.

:)
 
  • Like
Reactions: AlexMaximus

AlexMaximus

macrumors 6502a
Aug 15, 2006
821
231
A400M Base
Slot 2 is the I/o Crest SI_PEX40129. Dual M.2 to PCIe x8. On there I have a 960 Pro boot and SM951 scratch. It's basically one half of a 7101A at half the price. ~3000MB/s.

The Sonnet Tempo SATA maxed out ~950MB/s for 2-drive RAID 0 sequential(not sure if it was drive or interface limit). I needed high random I/O numbers and 8TB total capacity, so 4x2TB in a split configuration made sense. Only other way to get 8TB on SATA would've been all 4 drives on internal sleds, with a performance penalty for sequential performance or 2x4TB on the Sonnet card for way more $ and a massive random IOPS penalty.

10.13 and later does not support booting from any RAID.

There's a few ways to do this, depending on what you're trying to accomplish. With BootROM 140.0.0.0.0, Slot 2 will now link up at PCIe 2.0(5gbps) speeds for NVMe drives.

You don't want your NVMe drive on slot 3 or 4 since any activity on the other slot will rob bandwidth from the NVMe drive. Slots 3 and 4 share the same x4 link. Accelsior plus USB3 doesn't add up to 1500MB/s, so they will play nice together on a x4 link.

Best bang for the buck:
Slot 1 RX 580
Slot 2 Lycom+Samsung NVMe
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S

Max performance:
Slot 1 RX 580
Slot 2 SI_PEX40129+ 1 or 2 Samsung NVMe
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S

If you want boot screens, the port arrangement on the R9 280 I had was basically single-slot. You could creatively mount it into slot 4 while losing the space of drive bays 3 and 4. Would require removing the R9 280's bracket, chopping off the 2nd slot area of the bracket, and reinstalling the bracket. Good news is the bracket is a cheaply replaceable part. Buying a dead R9 280 from eBay and chopping up that donor card's bracket would be wise. Powering both the 280 and a 580 would require an additional mod that's commonly discussed on this forum.

The I Want It All option:
Max performance:
Slot 1 RX 580
Slot 2 SI_PEX40129+ 1 or 2 Samsung NVMe
Slot 3 USB 3 Card
Slot 4 Modded R9 280 also obstructing bays 3 and 4.
SATA SSD in optical bay or bay 1/2.

Many many thanks for your detailed answer. I was not aware that the Crest SI_PEX40129 works with Mac and provides boot capability. I would love to get the Crest card, however here is one short question for you before I pull the trigger.

At the moment I use two AHCI blade SSDs (1x941 & 1x951) in two adapters (PX1&HXP), occupying two PCIe slots.
If I get the Crest card, does this mean I can save one PCIe slot and:

- Maintain boot capability
- Maintain a 1500 MB/s speed for those AHCI SSD blades (that cant go faster anyways)
- Gain one PCIe slot
- Maintain Windows / Bootcamp capability

If you could confirm at least three times yes, I would be glad to pull the trigger on the Crest card.
Is the cooling fan real loud or does it work fine?

https://www.amazon.com/CREST-SI-PEX40129-Ports-Bifurcation-Controller/dp/B07HYZY7P2

Much appreciated, hope you can tell me a bit about your experience with the crest card. The one in the link above is the one you use?
 
  • Like
Reactions: macjunkie2013

Slash-2CPU

macrumors 6502
Dec 14, 2016
299
156
New Orleans, USA
Hey Slash-2CPU, several great suggestions.

My mac has the Pixlas mod so I think powering both cards (280 + Vega 64 eventually) should be fine? Did not think of moving the 280x to slot 4, that might work..

So to be clear you are using two SSD's in the SI_PEX40129, they are not RAID just simply boot + scratch, clever! I might just get the SI_PEX40129 and add one SSD for now. Hmmm....

In regards to your RAID, the combined drives give you fast random I/O because part of it is SATA?
Pixlas mod will allow powering the cards. You may get over-current shutdowns if you run both GPU's maxed out. I'm not sure.

On the SI_PEX40129, they have to be non-RAID so I can boot Mojave. Mojave can't boot to RAID.

All four SSD's in the RAID are SATA. Two are on onboard SATA. Other two are on the Sonnet SATA card. Having 4 drives instead of 2 gives better random I/O(also gives better steady-state performance and better long-duration write). Having the array split across two SATA controllers allows me to get >700MB/s sustained.
[doublepost=1542994092][/doublepost]
Many many thanks for your detailed answer. I was not aware that the Crest SI_PEX40129 works with Mac and provides boot capability. I would love to get the Crest card, however here is one short question for you before I pull the trigger.

At the moment I use two AHCI blade SSDs (1x941 & 1x951) in two adapters (PX1&HXP), occupying two PCIe slots.
If I get the Crest card, does this mean I can save one PCIe slot and:

- Maintain boot capability
- Maintain a 1500 MB/s speed for those AHCI SSD blades (that cant go faster anyways)
- Gain one PCIe slot
- Maintain Windows / Bootcamp capability

If you could confirm at least three times yes, I would be glad to pull the trigger on the Crest card.
Is the cooling fan real loud or does it work fine?

https://www.amazon.com/CREST-SI-PEX40129-Ports-Bifurcation-Controller/dp/B07HYZY7P2

Much appreciated, hope you can tell me a bit about your experience with the crest card. The one in the link above is the one you use?
- Maintain boot capability
Yes. Those are AHCI, not NVMe, so you can even boot with older BootROM. You don't need 140.0.0.0 update.

- Maintain a 1500 MB/s speed for those AHCI SSD blades (that cant go faster anyways)
Yes. The SI-PEX40129 can move ~3000MB/s between Slot 2 and the cards. Another way to think is that there's 3000MB/s available, shared between the two m.2 slots. Using the card in Slot 3 or 4 will limit the card to ~1500MB/s

- Gain one PCIe slot
Yes.

- Maintain Windows / Bootcamp capability

Yes. No drivers. The SI-PEX is a PCIe switch, much like an ethernet switch. It's essentially transparent to the OS. Interestingly, there is a PCIe switch on the motherboard that shares the PCIe x4 link between slots 3 and 4. That one also is also transparent and needs no drivers.

The cooling fan was audible but not loud. I unplugged the fan and watched with a temperature probe for an hour while I transferred between the m.2 drives at max speed. Stayed under 50°C. Didn't plug the fan back in. With the dedicated PCIe bay fan in the Mac Pro, you get constant airflow across the card. The card's onboard fan would be necessary if you had a case with poor airflow or if the card was sandwiched between two other large, hot cards. I have the SI-PEX in Slot 2 with the tiny USB 3.1 card above it in Slot 3 to allow for good airflow.
 

Eneco

macrumors regular
Jul 1, 2018
101
14
The cooling fan was audible but not loud. I unplugged the fan and watched with a temperature probe for an hour while I transferred between the m.2 drives at max speed. Stayed under 50°C. Didn't plug the fan back in. With the dedicated PCIe bay fan in the Mac Pro, you get constant airflow across the card. The card's onboard fan would be necessary if you had a case with poor airflow or if the card was sandwiched between two other large, hot cards. I have the SI-PEX in Slot 2 with the tiny USB 3.1 card above it in Slot 3 to allow for good airflow.
Isn't the fan there to cool the ASM2824 controller chip? Is it wise to kill off its cooling without being able to measure its temperature? Did you leave the heatsink cover open for a better airflow?
 
  • Like
Reactions: macjunkie2013

Slash-2CPU

macrumors 6502
Dec 14, 2016
299
156
New Orleans, USA
Isn't the fan there to cool the ASM2824 controller chip? Is it wise to kill off its cooling without being able to measure its temperature? Did you leave the heatsink cover open for a better airflow?

I measured the temp. After an hour of max load and no overheating, I was satisfied. ASM2824 is rated to 100°C.

The “cover” is aluminum and integral to the heat sink.

Wise? Not much about using a nearly decade-old Mac as my main workstation is wise. It’ll probably shorten the life of the chip from 15 years to only 6-10 years. . It will outlive it’s useful life in any case.
 
  • Like
Reactions: macjunkie2013

macjunkie2013

macrumors member
Original poster
Jun 9, 2013
43
47
You Ess Eh
Hey Slash-2CPU, thank you for the detailed feedback. Also thanks to AlexMaximus for additional detailed questions.

I decided to go ahead and get the SI_PEX40129 and two XPG SX8200 PCIe NVMe Gen3x4 M.2 drives a 480gb and 960gb to use as boot and scratch. Rakuten has them on sale today for $75 and $155.19 so it seemed like a good time to jump on it.

With all the upgrades, my Mac Pro will hopefully look like:
Slot 1 Sapphire Vega 64
Slot 2 SI_PEX40129 w 2 XPG SX8200
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S or Modded R9 280 also obstructing Drive bays 3 & 4

I am pretty sure I can find a blank or comparable card bracket as a local PC parts place that I can drill or modify to fit the 280x. Then keep the stock one, just in case I will not need the 280x.

One last question? To get the best onboard SATA performance would using 3 SSDs to the CDBay, DriveBay1 and DriveBay2 set up in Raid 0 reach 630-700 MB/s. I currently have 3x 5.25 drives (7200RPM barracudas) but imagine SSD would draw less power, be faster, and more reliable?

Cheers

JH
 

Slash-2CPU

macrumors 6502
Dec 14, 2016
299
156
New Orleans, USA
Hey Slash-2CPU, thank you for the detailed feedback. Also thanks to AlexMaximus for additional detailed questions.

I decided to go ahead and get the SI_PEX40129 and two XPG SX8200 PCIe NVMe Gen3x4 M.2 drives a 480gb and 960gb to use as boot and scratch. Rakuten has them on sale today for $75 and $155.19 so it seemed like a good time to jump on it.

With all the upgrades, my Mac Pro will hopefully look like:
Slot 1 Sapphire Vega 64
Slot 2 SI_PEX40129 w 2 XPG SX8200
Slot 3 USB 3 Card
Slot 4 OWC Accelsior S or Modded R9 280 also obstructing Drive bays 3 & 4

I am pretty sure I can find a blank or comparable card bracket as a local PC parts place that I can drill or modify to fit the 280x. Then keep the stock one, just in case I will not need the 280x.

One last question? To get the best onboard SATA performance would using 3 SSDs to the CDBay, DriveBay1 and DriveBay2 set up in Raid 0 reach 630-700 MB/s. I currently have 3x 5.25 drives (7200RPM barracudas) but imagine SSD would draw less power, be faster, and more reliable?

Cheers

JH
The SX8200’s aren’t quite as fast as a 970 Pro, but for most use cases, the difference won’t matter. The SX8200’s will be much faster than your 941/951 drives.

For replacing platter data storage drives, look at the Micron 1100 series of SSD’s. They can easily max out the internal bays speeds, and are basically Crucial drives in less pretty packages.

Onboard SATA ports are good for 260MB/s each and 600-700MB/s total. A 3-drive SSD RAID 0 array should easily max out both.
 
  • Like
Reactions: macjunkie2013

AlexMaximus

macrumors 6502a
Aug 15, 2006
821
231
A400M Base
Pixlas mod will allow powering the cards. You may get over-current shutdowns if you run both GPU's maxed out. I'm not sure.

On the SI_PEX40129, they have to be non-RAID so I can boot Mojave. Mojave can't boot to RAID.

All four SSD's in the RAID are SATA. Two are on onboard SATA. Other two are on the Sonnet SATA card. Having 4 drives instead of 2 gives better random I/O(also gives better steady-state performance and better long-duration write). Having the array split across two SATA controllers allows me to get >700MB/s sustained.
[doublepost=1542994092][/doublepost]

- Maintain boot capability
Yes. Those are AHCI, not NVMe, so you can even boot with older BootROM. You don't need 140.0.0.0 update.

- Maintain a 1500 MB/s speed for those AHCI SSD blades (that cant go faster anyways)
Yes. The SI-PEX40129 can move ~3000MB/s between Slot 2 and the cards. Another way to think is that there's 3000MB/s available, shared between the two m.2 slots. Using the card in Slot 3 or 4 will limit the card to ~1500MB/s

- Gain one PCIe slot
Yes.

- Maintain Windows / Bootcamp capability

Yes. No drivers. The SI-PEX is a PCIe switch, much like an ethernet switch. It's essentially transparent to the OS. Interestingly, there is a PCIe switch on the motherboard that shares the PCIe x4 link between slots 3 and 4. That one also is also transparent and needs no drivers.

The cooling fan was audible but not loud. I unplugged the fan and watched with a temperature probe for an hour while I transferred between the m.2 drives at max speed. Stayed under 50°C. Didn't plug the fan back in. With the dedicated PCIe bay fan in the Mac Pro, you get constant airflow across the card. The card's onboard fan would be necessary if you had a case with poor airflow or if the card was sandwiched between two other large, hot cards. I have the SI-PEX in Slot 2 with the tiny USB 3.1 card above it in Slot 3 to allow for good airflow.
Outstanding! Thank you so much for this clarification to Slash & Macjunky. I will get the Crest card as soon as possible once it Becomes available on Amazon. The new freed up PCIe Slot will be used for the sonnet Dual USB-C Card to allow ultrafast IO to external T5 Samsung SSDs. This is amazing, it keeps getting less atractive to switch from cMP to any other Apple product offering.
 
  • Like
Reactions: macjunkie2013

Slash-2CPU

macrumors 6502
Dec 14, 2016
299
156
New Orleans, USA
Outstanding! Thank you so much for this clarification to Slash & Macjunky. I will get the Crest card as soon as possible once it Becomes available on Amazon. The new freed up PCIe Slot will be used for the sonnet Dual USB-C Card to allow ultrafast IO to external T5 Samsung SSDs. This is amazing, it keeps getting less atractive to switch from cMP to any other Apple product offering.

The Sonnet USB card maxes out around 766MB/s plugged into a 4,1/5,1 Mac Pro.
 
  • Like
Reactions: macjunkie2013