Here's more legal way to load unsigned driver without test mode. DSEFix as I mentioned before doesn't work. That's because of PatchGuard that prevents patching the kernel. A lot of tools for disabling it doesn't work with the latest version of Windows, but I found one that is working. By disabling PatchGuard in real time, we can disable DSE to load driver and then enable it, so we won't have problems with Anti cheats.
You need to follow these steps:
1. Install original Nvidia Driver.
2. Download
DSEFix and
Shark from Github.
3. Move dsefix.exe and Shark folder to C:\ (to make it easier).
4. Copy nvlddmkm.sys from System32 to DifferentSLIAuto folder.
5. Patch nvlddmkm.sys with DifferentSLIAuto.exe or HexEditor (depending on version of driver).
6. Boot into safe mode.
7. Change the driver in System32 to the modified one.
8. Reboot computer.
9. Open CMD as admin and Device Manager.
10. Go to Shark folder and run it from cmd. → cd C:\2018-12-27-19-52-00 and Shark.exe
11. Wait 2 or 3 seconds and run dsefix.exe from cmd. → dsefix.exe
12. Re-enable Nvidia driver in Device Manager by right clicking on your GPUs, selecting disable and then enable.
13. Go to Nvidia Control Panel and turn on SLI.
(If you end up with Nvidia Control Panel crash, just restart the computer, load driver by doing steps 9,10,11,12,14 and SLI will be enabled)
14. Run DSEFix from cmd but use -e argument. → dsefix.exe -e
15. Success!
Redo points 9,10,11,12,14 on every boot in order to load the driver.
I might write a simple script to do these steps automatically on every boot. Anyways, like in previous method, SLI is working perfectly fine and Anti Cheat doesn't complain. It's more complicated than previous one but I feel better about it
I used Windows 10 17134 and Nvidia Driver 342.01.