Unreal engine 5.0 problem with multi GPU for others programs viewports


I installed UE 5.0 to test it and yes, it’s good but to much powered for my graphics cards (GTX 970, not use my 2x GTX 1070 TI in my 2nd and 3rd slot).

So before I remove it, I tried to test some models from my Blender’s projects and I found a big problem, multi gpu rendering no more works in my viewport (still in final render mode but only in viewport works with one gpu only). I removed it but still the same problem.

I know it’s UE that made the problem because worked just before I started the first time UE 5.0. Also in the first run, it crash and send me a message to allowed it to install more package when it restarted. So I said yes and since, I have the problem.

Could you tell me what was installed and what to remove or changed in regedit or in other place to be able again to use my multi gpu for my work in viewport ? I have also a few impact in games, lags I not have before.

Thank you very much,
Best Regards,


The error here (custom build of Blender by E-Cycles but legacy Blender, same problem) :