Hello guys,
I have a PC with two GPU's: PowerColor RED DRAGON Radeon RX 570 4GB and MSI Radeon RX 580 DirectX 12 RX 580 ARMOR 4GB.
On stock BIOS, I get 17.5 Mh/s on the 570 and 18.5 on the 580. I know I'm supposed to get at least 22 Mh/s and 24 Mh/s on each, respectively. When I modified the time straps to 1500, the hashrate improved to 20 and 20.9.
I tried many many many, and I mean many variations of core clock and memory clock with no luck. The memory clock doesn't seem to affect the hashrate at all. The core clock improves the hashrate slightly when increased to 1450. However, I wouldn't think it would justify the extra power it withdraws, as well as the extra heat on the card. So I kept the memory and core clocks at stock values.
http://www.imagebam.com/image/66cb7b725426983
I used to own three ASUS RX 580's but my god damn motherboard burnt and broke them. I used to get 24.5 Mh/s on each of them with 1500 timing straps and 1450 core clock and 2020 memory clock.
P.S. I'm mining from Saudi Arabia. Could the ping be affecting my hashrate? If so, it still doesn't explain why I got a lot better performance from the ASUS RX 580's.

Please help me. I'm stuck so bad.