Lenovo G40-70, PE4C, Radeon R7 240 - Sort of working

[andr01dm]

Hello.

 

I have a Lenovo G40-70 that I'm trying to add an eGPU to, it has an Intel Core i7-4510U CPU, 8GB of RAM, and onboard Intel HD Graphics 4400.  I bought a Bplus PE4C v4.1 with the M.2 A/E key, and a Sapphire Radeon R7 240.  The power supply is an Antec ATX 430W.

 

I started trying to get it running on Win 10 64bit, but as that was installed with UEFI I couldn't run DIY eGPU.  I've since installed Win 8.1 Pro 64bit using "Legacy" mode.  For testing I'm using HWiNFO64 to check the status of the system's PCI Express bus.. the tree for which looks like this:

 

Bus

  - PCI Bus #0

    - Intel Lynx Point-LP - PCI Express Root Port #3

      - PCI Express x1 Bus #1

         - RealTek Semiconductor etc. etc.

    - Intel Lynx Point-LP - PCI Express Root Port #4

      - PCI Express x1 Bus #2

 

Bus #2 is where my laptop's Wifi was plugged in, and has been swapped out for the eGPU.

 

At first I had no luck at all with getting the eGPU to show up.  So I tried going through every combination of Delay and Settings configuration of the switches on the PE4C.  I tried booting with the wifi installed, sleeping, swapping in the powered up eGPU and nothing.  Tried booting with the eGPU powered up, booting with it powered off.  Still nothing.  Tried taping over line 22 on the PE4C's key.  No change.

 

I purchased the DIY eGPU app and have been trying to figure it out, but initially I wasn't able to get the eGPU to appear in DIY either.

 

I'm not 100% certain what happened but during yet another boot into DIY, with the PE4C switches set to stock.. first position on each switch.. no special power up on the PE4C.. suddenly my eGPU was there!  It had found it!!  I have no idea what had changed, but it was working.

 

I ran a few of the commands in DIY eGPU which only work on a found eGPU.  Didn't really understand any of the output though.

 

So I crossed my fingers and rebooted into Windows and found that it was still working!  The video card showed up in HWiNFO, so  I installed video drivers, rebooted, still working.  I had video out put to both the external monitor and my laptop's screen.. dual monitors, not mirrors.  Thinking the worst was over I began setting up Steam.  A short time later my external monitor suddenly cut out, and then my laptop locked up.

 

Reboot.  The eGPU was still working.. but my internet connection was messed up for about 10 min, before finally coming back.  The LAN hardware is in PCIe Bus #1 so maybe there was some kind of 'crosstalk' with the video card on PCIe Bus #2?  About 15 min later, the output to the external monitor died and the laptop locked up again.

 

I shut down, removed the PE4C's key from the PCIe slot and rebooted.  The onboard GPU worked normally and no crashes.  A while later I re-installed the PE4C's key and found that my system could no longer find the eGPU.

 

I've been poking around this forum looking for possible solutions, and booting into DIY eGPU to try and make sense of it all.  But I think it's time to reach out and see if anyone can suggest a course of action...

 

I've tried to run "Compact All except..." in DIY with the default range, and it appears to run, but then I'm unable to return to the GUI due to "C: DOS area: sector not found" error.  So I ran the command which logs the compact attempt and I'm attaching the C:\diag folder to this post.

 

Please let me know if you have any suggestions or if there's any more info you'd like me to provide.  I have photos of the handful of tests I ran in DIY when the video card was detected, and I can provide them if you think they might help.

 

Thank you.

diag.zip

[Tech Inferno Fan]

Diag shows no eGPU. Refer to following for suggested procedures to get eGPU detected:

 

[andr01dm]

9 hours ago, Tech Inferno Fan said:

Diag shows no eGPU. Refer to following for suggested procedures to get eGPU detected:

 

 

Hi, thank you for your reply.

 

I've gone through all of the steps on the linked page:

 

PCIe Ports->enable to enable the missing port.
- the required port is being found in DIY eGPU:  [email protected]

 

 eGPU does not get detected
 Overcome mPCIe whitelisting by booting with the wifi card and then hotswapping in the eGPU. That way the BIOS will enable the mPCIe port to work.
 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?
- no eGPU detected in Device Manager or HWiNFO64

 

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?
- 5 min of polling, no eGPU detected

 eGPU still not detected - set the PSU to be permanently on
- [email protected] still shows up in DIY eGPU, but no eGPU detected
- F5, 5 min of polling, no eGPU detected

 eGPU still not detected - a non-standard mPCIe implementation by your vendor?
PERST# mPCIe pin 22 may need to be isolated due to a non-standard implementation by your notebook vendor:
- taped over pin 22, booted into DIY
- [email protected] no longer shows up
- Enable port > p4
- [email protected] and [email protected] show up
- F5 to scan for eGPU
- eGPU not found
- removed tape over pin 22, reinserted eGPU's key
- now p4 doesn't appear on boot, unless PSU is powered on before boot, even then the eGPU is not detected
- let it sit powered off for a few minutes, now the p4 is appearing even with PSU off before boot, still no eGPU detected

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.
- the only other laptop I have access to doesn't use the A/E key.. may not even be a PCIe slot.

- the eGPU & video card ran for about half an hour yesterday, though they were unstable.  So the video card at least seems to be working fine.

[andr01dm]

Follow up.

 

They've RMA'd my non-working Bplus PE4C v4.1, and I have a new one now.  It worked first time!  Booted into DIY eGPU and it was detected immediately.  I had to run "Compact All" before Windows 10 would see it, but it works just fine now.  Stable.  I've run a few games and all is well.

 

Now I need to put together a less jury-rigged set up.  Get a case wrapped around the eGPU & maybe a 12v power brick instead of the ATX power supply I 'borrowed' from one of my other projects.

[Tech Inferno Fan]

40 minutes ago, andr01dm said:

Follow up.

 

They've RMA'd my non-working Bplus PE4C v4.1, and I have a new one now.  It worked first time!  Booted into DIY eGPU and it was detected immediately.  I had to run "Compact All" before Windows 10 would see it, but it works just fine now.  Stable.  I've run a few games and all is well.

 

Now I need to put together a less jury-rigged set up.  Get a case wrapped around the eGPU & maybe a 12v power brick instead of the ATX power supply I 'borrowed' from one of my other projects.

 

@andr01dm,  nice work in getting it up and running. We don't have a previous Lenovo G40-70 eGPU implementation writeup. Did you want to create one putting in the details of your pioneering findings so other owners of this notebook can confidently proceed to add an eGPU to theirs too?

 

[andr01dm]

I wrote a 'how-to' post about my setup: