You can't use DirectX 9 period with Dolphin 5.0, and honestly said you don't want to use it either. DirectX 9 is horrible outdated and fundamentally flawed. If you can not use Dolphin 5.0 because of lacking hardware power, then I would simply suggest not to bother with Dolphin. You are not going to have an enjoyable experience with such low specs and outdated version. You should really upgrade your hardware and you should update to 5.0 before attempting to use Dolphin again (anything lower than 5.0 is not supported anymore).
Sorry if it sounded blunt, but that is the reality. Emulation is not the same as playing your native PC games. Keep in mind that you are not emulating a game, but the entire console itself. This takes power, a lot. You could always stick to N64 or GBA emulation which is a lot lighter to run.
Sorry if it sounded blunt, but that is the reality. Emulation is not the same as playing your native PC games. Keep in mind that you are not emulating a game, but the entire console itself. This takes power, a lot. You could always stick to N64 or GBA emulation which is a lot lighter to run.