I'm user of RX 470(570) 4GB. The problem is, the DAG file size is already getting too big. Windows 10 takes about 0,5GB of VRAM, and the epoch over #317 is already too big, and the miner is starting to take memory from system RAM, so the speeds slows down from 27-28 to 19-20MH/s.
Can i somehow reduce reserved VRAM of Windows 10?
And can i choose what DAG epoch to use? Because sometimes when the miner chooses smaller epoch #317 the speed is 27,5 MH/s, but after some time it switches to epoch over #318 and it's bigger so the memory is getting choked and the speed is going down to 19-20 MH/s.
I've found a workaround for this.
If you activate iGPU (internal gpu in your cpu) and use the hdmi on the motherboard, then Windows won't allocate that memory from your mining gpu. If you don't have internal graphics on your cpu, the workaround works if you put a gpu with more than 4gb vram as the first (or a gpu that you only use for being first and not for mining).