Multitasking on Nox Emulator

I've tried playing multiple emulators before but all their settings were set to Low (uses less CPU cores and RAM), and I've been playing 1 game only: Ragnarok M. Recently though, I tried to add more emulators and some are using higher settings.

Right now, I have 3 emulators running. 2 are playing Ragnarok M and in 1, I'm playing Real Racing 3. I'm currently downloading Asphalt 9 and hoping it would work, because I tried it earlier but it just crashes (probably because I was using the Android v 4 emulators). I'm going to try the game again on v5 or v7 emulators, maybe that'll do the trick, but I'm still waiting for my download, our internet's not that fast.

For the meantime, I'll enjoy playing Real Racing 3. I know I should get a desktop racing game but my GPU can't really handle it.