Re: AMD Mem Tweak XL - Read/modify timings/pp/straps on the fly
Can somebody explain to me WTF is going on with my GPUS? 
so using teamredminer latest version while having my vega 64 (nitro+) on stock bios core1100@ 820mV mem 1100 @ 850 mV
with memory timings cl 22 ras 35 rcdwr 12// rcab 44 rcpb 44 // rrds rrdl 5// faw 20 //REF 17550//RFC 247
I get 51Mh/s @ about 140 watts.
When I downgrade my bios to a vega 56 one (so from vega 64 TO vega 56, not the other way arround!)
1) the memory timings mentioned above dont work
2) this memory timings work 0 --RAS 26 --RCDRD 13 --RCDWR 12 --RC 38 --RP 12 --RRDS 3 --RRDL 5 --RTP 6 --FAW 12 --CWL 8 --WTRS 4 --WTRL 9 --WR 14 --REF 20600 --RFC 244
and with the above ("2") and core at 1100 810Mv and mem 1045 @ 82Mv The damn thing runs at 55Mh/s while consuming less power!!!
unfortunately I cant got more than 1045 though (despite when being on vega 64 bios I cat get easilty to 1100)
but the question is HOW DOES THIS WORK? can anybody give me a kinda technical explanation as to why with a downgraded bios + slower mem frequency the GPU performs so much better ?
Can I make it even better?
so using teamredminer latest version while having my vega 64 (nitro+) on stock bios core1100@ 820mV mem 1100 @ 850 mV
with memory timings cl 22 ras 35 rcdwr 12// rcab 44 rcpb 44 // rrds rrdl 5// faw 20 //REF 17550//RFC 247
I get 51Mh/s @ about 140 watts.
When I downgrade my bios to a vega 56 one (so from vega 64 TO vega 56, not the other way arround!)
1) the memory timings mentioned above dont work
2) this memory timings work 0 --RAS 26 --RCDRD 13 --RCDWR 12 --RC 38 --RP 12 --RRDS 3 --RRDL 5 --RTP 6 --FAW 12 --CWL 8 --WTRS 4 --WTRL 9 --WR 14 --REF 20600 --RFC 244
and with the above ("2") and core at 1100 810Mv and mem 1045 @ 82Mv The damn thing runs at 55Mh/s while consuming less power!!!
unfortunately I cant got more than 1045 though (despite when being on vega 64 bios I cat get easilty to 1100)
but the question is HOW DOES THIS WORK? can anybody give me a kinda technical explanation as to why with a downgraded bios + slower mem frequency the GPU performs so much better ?
Can I make it even better?
So, how I see it is that tighter timings matter more than overall clock speeds. But you cant have as tight as timings on faster memory clocks.
Also the vega 64 bios enables the GPU to apply more voltage to the memory for faster clocks. The actual memory modules are the same on the samsung 56 and 64 so it's only a bios thing.