[Sticky] [GUIDE] error 43 + other detection, bootup and stability problems mPCIe/EC/NGFF.M2  


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Joined: 2 months  ago
Posts: 255
December 23, 2016 1:59 pm  

I've had a stack of recurring offline questions from users with problems getting mPCIe, expresscard or NGFF.M2 eGPU adapter interfaces working. This includes GPU-Z not reporting no clock details, error 10/43 or even not being detected at all. Overall it's more troublesome getting mPCIe working than say expresscard or Thunderbolt.

Below are common problems and how to correct them:


set the PSU to be permanently on to help troubleshooting

BPlus eGPU and EXP GDC eGPU adapters only enable PSU power upon detecting a PCIe signal. This can cause a race condition where the eGPU isn't ready to go when the PCIe CLKRUN signal is asserted.

The fix is to jumper the PSU so it's permanently on rather than being eGPU adapter managed. BPlus PE4C 3.0 can set a the PWR ON shown with yellow arrow on the far left here to do that. For all other eGPU adapters, Depending on the PSU you are using refer to the following doco on how to do that.

ATX PSU: http://aphnetworks.com/tutorials/psu_paperclip_trick
Dell DA2: http://www.silentpcreview.com/forums/viewtopic.php?p=526066#p526066

Doing this will greatly assist further troubleshooting.


error 43: incorrect eGPU initialization due to PSU mistiming

Use GPU-Z software to check if your clock information is being reported correctly. If not, then your eGPU isn't initialising properly. This can happen due to incorrect clock timings. Ensure you have set your PSU to be permanently on as per previous step.

 1. Set the delays on the eGPU adapter (CTD/PTD - EXP GDC or CLKRUN/PERST# on PE4L/PE4C). Boot into Windows or Setup 1.30. Is the eGPU detected with correct clock info reported by GPU-Z?


error 43: running a NVidia dGPU and eGPU

If you have NVidia dGPU as well as NVidia eGPU then it's likely because of having the mobile NVidia and desktop NVidia drivers loaded simultaneously. Proceed to disable your dGPU, uninstall ALL your NVidia drivers, use "DDU" to disable automatic driver installation and clean NVidia registry entries. Then do a 'clean' install of the latest NVidia desktop driver.


error 43: NVidia driver 372.90 and newer on non-hotpluggable mPCIe/M2 interfaces

NVidia driver 372.90 and and newer have been found to cause an eGPU error 43 when hosted on non-hotpluggable interfaces (mPCIe, M2). So revert to 372.70 while testing to get around that. As of 375.xx, this problem persists and may be part of a larger strategy by NVidia to eliminate these hacky eGPUs.

REF: https://egpu.io/forums/expresscard-mpcie-m-2-adapters/nvidia-is-killing-off-mpciengff-m2-egpus-error-43-with-372-90/


A black bootup screen or ACPI_BIOS_ERROR windows bootup BSOD

Here the BIOS doesn't know what to do or mangles the ACPI when it sees an eGPU. The latter preventing Windows from loading successfully. So the solution is to not let the BIOS see the eGPU. Two ways of doing that:

1. Set the delays on the eGPU adapter (CTD/PTD - EXP GDC or CLKRUN/PERST# on PE4L/PE4C). Boot into Windows or Setup 1.30. Is the eGPU detected?

2. Halt Windows loading with F12/F8 hotplug your eGPU adapter interface. Is the eGPU detected? Alternatively, boot into Setup 1.30 , hotplug your eGPU adapter interface, hit F5 to scan for the eGPU. Is the eGPU detected?


mPCIe port that hosted the wifi card disappears when connecting an eGPU in it's place

Use the Setup 1.30 PCIe Ports->enable to enable the missing port.


mPCIe/M2: eGPU doesn't get detected

Likely due to BIOS whitelisting preventing the port from being enabled when a non vendor device is detected. Overcome by booting with the wifi card and then hotswapping in the eGPU. That way the BIOS will enable the mPCIe port to work. A few ways to do that:

1. Boot with wifi card into Windows, sleep system, swap wifi card for mPCIe eGPU adapter and ensure eGPU is powered on, resume system. Do a device manager scan in Windows. Is the eGPU detected?

2. Boot with wifi card into Setup 1.30. *carefully* hotplug the eGPU adapter in place of wifi card. Hit F5 to rescan the PCIe bus. Is the eGPU detected?

If this enables detection then avoid this tedious hotswapping by seeking a unwhitelisted modified BIOS for your system from say http://www.bios-mods.com OR test the Setup 1.30's PCI ports->undo_whitesting feature.


mPCIe: eGPU still not detected - a non-standard vendor port implementation?

PERST# mPCIe pin 22 may need to be isolated due to a non-standard implementation by your notebook vendor causing CLKRUN/CLKREQ mistiming.


eGPU still not detected: faulty hardware?

If you still don't get detection then test the video card and eGPU adapter in another machine to confirm neither is faulty.


"NVidia driver stopped responding" intermittent messages: can't run Gen2 signalling

EXP GDC, PE4H 2.4 and PE4L 1.5 all use a socketted cable and therefore are not true Gen2 compatible device. This error indicates there was transmissions errors.

The solution is either to get a better Gen2-compliant eGPU adapter such as PE4C V3.0 or PE4L 2.1b (both with soldered cable), or downgrade your link from Gen2 to Gen1 using BIOS options or Setup 1.30.

Edited: 1 week  ago

DIY eGPU Setup 1.31 [was 1.30]eGPUing since '09

New Member
Joined: 1 week  ago
Posts: 2
January 7, 2017 12:53 pm  

I have PSU turned on (i think) ... on EXP GDC v8 adapter is switch for atx pw, which makes power supply run without laptop turned on ... and clocks still dont work.



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