any way to lower rendering resolution for high fps?

any way to lower rendering resolution for high fps?
or custom resolution Similar to pcsx2.

its going to help many with older gpu or igpu user.

RPCS3 is not GPU bound in any way really. My GT555m never sees more than maybe 30 % usage in any game. If your GPU is modern enough to have good OpenGL 4 support it is very likely also fast enough.

Intel graphics are not supported, even on Kaby Lake and new drivers they are in general too buggy. Some games will run, but many will not. If games run the GPU is fast enough though.

You can however go into RPCS3 settings and just set it to 480p. Most if not every game should still work. It probably wont help much in general, but allegedly it does in some games.