Did you try setting "ubershaders" to 'hybrid' or 'exclusive'?
I don't know if it's still the case, but on Radeon GPUs it was recommended to use D3D for 'hybrid', though both Vulkan and D3D worked for 'exclusive'.
Normally 'exclusive' ubershaders is much more demanding on the GPU than 'hybrid' ubershaders, but an Rx 580 should have quite a bit of performance headroom at only 1360x768; yes you could "eat up" a good amount of that headroom by using higher internal resolutions, but at 768p you're going to start hitting diminishing returns at even just 3x IR and especially with anything past 4x IR.
I don't know if it's still the case, but on Radeon GPUs it was recommended to use D3D for 'hybrid', though both Vulkan and D3D worked for 'exclusive'.
Normally 'exclusive' ubershaders is much more demanding on the GPU than 'hybrid' ubershaders, but an Rx 580 should have quite a bit of performance headroom at only 1360x768; yes you could "eat up" a good amount of that headroom by using higher internal resolutions, but at 768p you're going to start hitting diminishing returns at even just 3x IR and especially with anything past 4x IR.
Dolphin 5.0 CPU benchmark
CPU: Pentium G3258 @ 4.5GHz 1.24v
GPU: Intel integrated
RAM: 4x4GB Corsair Vengence @ DDR3-1600
OS: Linux Mint of some variety + [VM] Win7 SP1 x64
CPU: Pentium G3258 @ 4.5GHz 1.24v
GPU: Intel integrated
RAM: 4x4GB Corsair Vengence @ DDR3-1600
OS: Linux Mint of some variety + [VM] Win7 SP1 x64