ePSXe needs 512MB of RAM at a maximum. PCSx needs 512MB but it can go up to 2GB. Chuwi has integrated graphics as far as I know.
I have an “atom-reactor” PC and sometimes it shutters with PCSx so I guess the issue is that PCSx is not really performance friendly.
Unfortunately, emulators are not the best.
PC Specs: 8GB RAM, I5 6500 CPU, GTX 760 Ti VGA