I'm having trouble getting 3 new 4TB WD SN850X blades to work in my Mac Pro 4,1 -> 5,1 and would really appreciate some advice...
Setup:
I'd be ready to simply declare that SN850X blades are incompatible with MP 4,1 or 5,1 machines, if it hadn't been for the initial (unrepeatable) partial success. Frankly I'd think I'd dreamt it, if I hadn't exported the System Report proving that one of the three SN850Xs was recognised during that initial boot.
Setup:
- Mac Pro 4,1 -> 5,1 (boot ROM 144.0.0.0.0, SMC 1.39f5)
- CPUs: 2 x X5690 = 12 core 3.46GHz
- RAM: 6 x 16GB 1333GHz ECC = 96GB
- GPU: Sapphire Pulse Radeon RX 580 8G GDDR5 (PCIe slot 2)
- NVMe host: Sonnet Fusion 4x4 M.2 silent (PCIe slot 1)
- macOS M.2 blade (Sonnet Fusion slot 1): Samsung 970 EVO Plus 500GB (rev. 2B2QEXM7) - OS drive (macOS 10.14.6, 18G9323) - been running flawlessly for years
- new M.2 blades (Sonnet Fusion slots 2-4): 3 x WD SN850X 4TB (3 x WDS400T2X0E-00BCA0 - 1 x DOM=11NOV22 SN= 22451... + 2 x DOM=18NOV22 SN=22461... all three are running latest available f/w 624311WD)
- 1st boot after installing, mac booted fine off the 970 EVO Plus, 1 of 3 SN850Xs were detected by the system. Disk Utility was able to format it APFS fine... Exported a System Report... Set about debugging the missing two SN850Xs by juggling the blades into different slots, removing unused peripherals etc...
- Subsequent boots, no SN850Xs detected by the PCIe bus in System Report or visible in Disk Utility. Diagnostic LEDs D1-D4 (nearest PCB outer edge) on the Sonnet Fusion 4x4 M.2 stay un-illuminated for slots containing an SN850X, but illuminate within 1 second of POST for the 970 EVO Plus. Diagnostic LEDs D7-D10 (furthest from PCB edge) on the Sonnet Fusion 4x4 M.2 illuminate for all blades immediately on PSU power on.
- Have never been able to replicate the initial partial success, even by returning to the initial h/w configuration.
- In a Windows 10 machine (Gigabyte GA-B85-HD3) the Fusion 4x4 M.2 with all three WD SN850X blades (but no 970 EVO Plus) behaved as expected and all drives were recognised by the system. Diagnostic LEDs D1-4 and D7-10 illuminated for all three SN850X drives.
- PRAM reset
- SMC reset
- Removing all other hardware, leaving only CPUs, RAM, GPUs, Fusion 4x4 M.2 and 1 SN850X - diag LED D1-4 remains un-illuminated after POST. I was not able to boot beyond POST without my macOS drive installed, and didn't try attaching USB boot media - I simply assumed that as diag LED D1-4 illuminated within 1 second of power on with the 970 EVO Plus, and never illuminated after post with the SN850X, that a PCIe connection had not been negotiated between the blade & Northbridge.
- Asking Sonnet for technical documentation for the states of the diag LEDs on the Fusion 4x4 - support has been responsive - awaiting further details.
- Asking WD support if they can put me in touch with their firmware engineering team to see if they can reproduce / fix the behaviour. Customer Support unhelpful, and informed me that the firmware is not user updatable, which I'm moderately confident is false. Awaiting reply to my support ticket from WD's "Advanced Tech Support".
I'd be ready to simply declare that SN850X blades are incompatible with MP 4,1 or 5,1 machines, if it hadn't been for the initial (unrepeatable) partial success. Frankly I'd think I'd dreamt it, if I hadn't exported the System Report proving that one of the three SN850Xs was recognised during that initial boot.
- Any advice / suggestions for debugging steps to try would be massively appreciated! Is there any possibility of increased compatibility by running a later OS, or boot-loader?
- My experience may be useful for updating the original wiki post w/r/t WD SN850X compatibility.
- I'm trying to optimise for high throughput of random reads (at low to mid QDs), and large TBW in my drive selection, so any suggestions for alternate, known compatible 4TB options would also be really appreciated.
- Are there any PCIe gen 4.0 blades known to work reliably in the MP 4,1 / 5,1 or MUST we in fact select PCIe gen 3.0 blades?
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