windows not showing 4th gpu

[Stratton Oakmont]

So i cannot get windows to show my 4th gpu.I have made sure my virtual memory is at 16000, reinstalled windows, reinstalled drivers.

its 100% not a hardware issue. I swapped out pci, usb, power supply cables with working ones to verify not hardware. also tried a different pcie slot. if i move the 4th gpu in place of #3 gpu the pc sees it still but not the 4th. therefore i know its not hardware related.

im running a msi 270a pro board, celeron processor, 4gb ballistix ram, 120gb solid state, 4 msi 1070 gpu on riser with corsaire platinum psu, running windows 10 pro

i have reinstalled nvidia drivers and checked for update. double checked virtual memory and bios settings. gen 2 and mining mode is on

i dont see any onboard graphics to turn off in settings.

msi afterburner only shows 3 out 4 gpu

[ncsupanda]

How do you have your PSU set up? If your PSU is not correctly set up you may not be sending enough power to the 4th GPU.
Does the 4th GPU turn on and run, but still is not found?

[amishmanish]

Okay this is a pretty bad issue. The solution is probably as stupid as it could be. I have no idea why it doesn't work or does when it does.
I cannot tell you if this will work for you or not.  What I can tell you is the archaic combination of steps thats supposed to magically solve this problem.

So first of all you boot without any of the cards attached and then erase the drivers completely. (There's a Driver removal  tool for that)
Next you install the blockchain drivers.
Now you get all your cards to detect one by one on the same primary slot. You would obviously have to shut down it 4 times. The point is to get them all to be detected at least once, one at a time.

Once that is done. You boot with just one card in the first slot. See in Device manager if its detected.
Shut down and add the second card to your second slot
Reboot and Device Manager should show the second card.
Shut down and add the third one to the third slot..
Reboot and Repeat for the 4th card. All cards should now get detected (hopefully).

Read the manual for motherboard available on the website to be sure that All 4 PCIE slots are free.
If you are using a single PSU, Distribute the power connectors as equally as possible between different 12V rails.
You can try these steps without Gen 2 and Mining mode initially.

These are just a few of the stupid sounding magic ingredients. Hope this helps

PS: This topic should be in the Altcoin mining section and not Bitcoin Technical section. Move it there.