Which M.2 PCIe X16 adapter card?

MisterAndrew

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MisterAndrew

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Maybe I’ll get that cheap single X16 card though and see if it works. Has anyone tested one? I know the PLX switch is necessary for pcie bifurcation (multiple SSDs on a single card), but is it also needed to enable the 3.0 X4 M.2 card to negotiate at 2.0 X16?
 

h9826790

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Maybe I’ll get that cheap single X16 card though and see if it works. Has anyone tested one? I know the PLX switch is necessary for pcie bifurcation (multiple SSDs on a single card), but is it also needed to enable the 3.0 X4 M.2 card to negotiate at 2.0 X16?
So far, the evidence point to that the PCIe switch is a requirement to let any PCIe 3.0 device correctly negotiate at PCIe 2.0 speed.

Without the switch, the device will automatically fall back to PCIe 1.0 speed.

And you won't get anything faster than PCIe 2.0 x4 for a single SSD. Even with the switch, it can only allow the PCIe 3.0 x4 SSD negotiate at PCIe 2.0 x4. But won't re-allocate other lanes' bandwidth to let it run at PCIe 3.0 x4.
 

MisterAndrew

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So far, the evidence point to that the PCIe switch is a requirement to let any PCIe 3.0 device correctly negotiate at PCIe 2.0 speed.

Without the switch, the device will automatically fall back to PCIe 1.0 speed.

And you won't get anything faster than PCIe 2.0 x4 for a single SSD. Even with the switch, it can only allow the PCIe 3.0 x4 SSD negotiate at PCIe 2.0 x4. But won't re-allocate other lanes' bandwidth to let it run at PCIe 3.0 x4.
Oh I see. So the ~1500 max speeds we are getting currently are PCIe 1.1 X4? And the ~3000 speed the Amfeltec Squid can attain are at PCIe 2.0 X4?
 

crjackson2134

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Mar 6, 2013
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1500MB/s is the max real world speed for a PCIe 2.0 x4 connected SSD.

If further fall back to PCIe 1.1 x4, the speed will further limited to 750MB/s.
Exactly right, I've tested it MANY times. Also when you place the device into a proper x4 slot, you will get significantly slower cold boot times. Placing the card in the x16 slot gives much faster boot times, but reduced performance otherwise.
 
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XNorth

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Feb 23, 2018
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For a single nvme blade, a cheap Lycom x4 pcie 3 is comparable to the expensive Amfeltec Squid x16 PCIe 2. Was interested in the Highpoint NVMe RAID but didn’t get a response from them about Mac support.
 

crjackson2134

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For those of you who have, or have tested the Squid, does the PLX cause a boot delay when placed into Slot2 (x16) in a 5’1.

I moved my SSUBX from Slot3 to Slot2 because the insane cold boot times in slots 3/4 were making me batty. Right now I have my choice of 2 min. Boot time w/1500 MB/s file transfers, or 14 sec. Boot times w/780 MB/s file transfers.

I’m trying to achieve both fast boot, and full speed x4 transfers. Not to mention the ablility to add NVMe storage devices with the Squid.

I have an adapter that will allow me to put my SSUBX into the Squid for booting, but if this card will cause a boot delay like placement in slots 3/4, then I’ll pass on this purchase.
 
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handheldgames

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For those of you who have, or have tested the Squid, does the PLX cause a boot delay when placed into Slot2 (x16) in a 5’1.

I moved my SSUBX from Slot3 to Slot2 because the insane cold boot times in slots 3/4 were making me batty. Right now I have my choice of 2 min. Boot time w/1500 MB/s file transfers, or 14 sec. Boot times w/780 MB/s file transfers.

I’m trying to achieve both fast boot, and full speed x4 transfers. Not to mention the ablility to add NVMe storage devices with the Squid.

I have an adapter that will allow me to put my SSUBX into the Squid for booting, but if this card will cause a boot delay like placement in slots 3/4, then I’ll pass on this purchase.
Besides the SLOOW boot, My SSUBX also hiccups at times and cold boots into recovery mode.

TIP: With the mac turned off, press power to turn it on. Immediately turn it off and back on. Taking this approach provides the fastest route to the desktop.
 

crjackson2134

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Besides the SLOOW boot, My SSUBX also hiccups at times and cold boots into recovery mode.

TIP: With the mac turned off, press power to turn it on. Immediately turn it off and back on. Taking this approach provides the fastest route to the desktop.
Cool tip... I’ll check it out...
 
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handheldgames

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14 seconds? That’s stellar. My 09 currently takes 20 seconds to chime and I’m lucky to see the login screen by 59 seconds with a 970pro or a sm951 in slot 3 or 4.

I’ll have to check boot times in slot 2 with the squid. I know I tested the ssubx in slot 2 and posted the results a couple years ago.

With your ssubx in slot 2, reset your pram and see if it fixes the bus speed. I seem to remember letting it chime 2x before releasing the keyboard to get the desired effect.
 
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crjackson2134

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14 seconds? That’s stellar. My 09 currently takes 20 seconds to chime and I’m lucky to see the login screen by 59 seconds with a 970pro or a sm951 in slot 3 or 4.

I’ll have to check boot times in slot 2 with the squid. I know I tested the ssubx in slot 2 and posted the results a couple years ago.

With your ssubx in slot 2, reset your pram and see if it fixes the bus speed. I seem to remember letting it chime 2x before releasing the keyboard to get the desired effect.
PRAM has no effect on its buss speed. Done it hundreds of times during testing. I too have stupid slow boot speed in slots 3/4 and just couldn’t take it anymore.

Recently I installed Win10 for the wife’s work. She works at a university so it’s mandatory. This means I reboot often, as I have no use for Windows and she has none foe macOS.

I don’t mind sharing but the slow boots were killing us both.
 

JedNZ

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Dec 6, 2015
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I don't have a squid, but I have my Samsung 850 EVO SSD in an Accelsior S SATA III PCIe adapter in Slot3, and I have noticed a huge difference in boot times when I actually have the boot drive selected in System Preferences > Startup Disk. If I do a PRAM reset, it clears the startup disk setting, so the next restart is painfully slow. But when I set the boot drive, magic, lights and desktop within 40 secs (boot chime in 10 secs, status bar completed in 15secs, enter user/pass and desktop appears in 10-15secs).
 

h9826790

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Apr 3, 2014
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Is that 14s start from the chime?

Sounds quite impossible if start from pressing the button.

The cMP take quite a few seconds to run POST, the more hardware, the slower the POST. With 48GB of RAM, multiple PCIe cards, it's quite hard to believe that the cMP can boot in 14s from pressing the button.

Anyway, if selecting boot drive in system preference doesn't help, you may try some PRAM / SMC reset with the bare card (no SSD onboard). That occasionally can fix this kind of slow boot issue.
 

crjackson2134

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Mar 6, 2013
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Charlotte, NC
Is that 14s start from the chime?

Sounds quite impossible if start from pressing the button.

The cMP take quite a few seconds to run POST, the more hardware, the slower the POST. With 48GB of RAM, multiple PCIe cards, it's quite hard to believe that the cMP can boot in 14s from pressing the button.

Anyway, if selecting boot drive in system preference doesn't help, you may try some PRAM / SMC reset with the bare card (no SSD onboard). That occasionally can fix this kind of slow boot issue.
Yes, from chime. My hardware detection takes ~8 seconds roughly. I don’t and can’t count that because simply changing or removing memory, HDDs, and other PCIe card’s effects it drastically. Even the PCIe SSD introduces an EXTREME hardware detection delay (not counting slow OS boot) when placed in Slot3on my system.

My point is this...

Restart from booted system > very fast
Powered off momentarily > fast but slower than restart
Cold boot, off extended period of time > slowest boot, real test

I get a boot chime in about 5~8 seconds with no keys pressed from a cold boot, regardless of SSD configuration. However, with the PCIe/SSUBX in slots 3/4, it hangs at the white screen from 1-2 minutes before the progress bar starts loading. In Slot 2, takes 14 seconds from BONG! to fullyloaded Desktop. The 5~8 seconds it takes for unrelated hardware devices to be detected are irrelevant to me, because the SSD in Slot 2 introduces no hardware detection delays. It’s the same even if I remove the device and boot from one of my other SSDs.
 
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iamtheonlyone4ever

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May 27, 2016
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Amazon had the HighPoint SSD1701 for a prime warehouse deal of $271 that was too good to pass up.

Hopefully it will work. Either way, I’m looking forward to clarify compatibility / performance / cooling capability.
so what happened? did Mac os recognized the card ??????
 

handheldgames

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Apr 4, 2009
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Pacific NW, USA
With a NVMe boot EFI firmware modded following the step-by-step Google Doc I was asked to write..

It works great as a bootable m.2 adapter delivering PCIe 3.0 speeds on the cMP with a 970 pro, connected as a 8.0Gt/s device with 3000MB/sec reads, 2000 MB/sec writes.

Mojave public beta installed on the Highpoint 7101a without issue. TRIM is also enabled by default.


Apple SSD Controller:



Samsung SSD 970 PRO 512GB:

Capacity: 512.11 GB (512,110,190,592 bytes)
TRIM Support: Yes
Model: Samsung SSD 970 PRO 512GB
Revision: 1B2QEXP7
Serial Number: xxxxxxxxxxxxxxxxx
Link Width: x4
Link Speed: 8.0 GT/s
Detachable Drive: No
BSD Name: disk2
Partition Map Type: GPT (GUID Partition Table)
Removable Media: No
Volumes:

EFI:

Capacity: 209.7 MB (209,715,200 bytes)

File System: MS-DOS FAT32
BSD Name: disk2s1
Content: EFI
Volume UUID: 0E239BC6-F960-3107-89CF-1C97F78BB46B

disk2s2:

Capacity: 511.9 GB (511,900,434,432 bytes)
BSD Name: disk2s2
Content: Apple_APFS
 
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