always do 80% max tdp or even lower, while increase the core to +100 or +150, mem only matter on algo such as ETH or ZCASH, not many algo require memory, most of the tiem i do the trick of -502 i get better hash
NOPE ... always is not good solution ... my guru told me when you go to much low on tdp it drasticly remove hashrate ... all you need is hashrate .. tdp is only for lowering of elecricity bills ... like 1080ti ... on stock tdp has 250w and is able to +250 even more on core (im now running on 100% tdp and +270 core) and its different if you have 180w and 870mh/s or 250w and 1gh/s coz in prise in el. it will be couple of dollars per month but you will increase your income by +20% and it will do hundreds
I DONT TELL: DONT LOWER TDP ... i only say that you need to configure your system to get same hashrate with lower power consumption but not much ... why you need lower el. bills when you "lost" realy big amout of money that way ... if you live in absurdly expensive state on el., then yes ofc ... but even in europe is only 0,15e for kwh ... its so much low ...
when you have rig, that eats 1kwh per hour, then it MUST have enourmouse hashrate
so IMO for OC/undervolt
1080ti - never undervolt, put +++++ in core what can this beast take (and ---- on mems, like -502)
1080 - dont know, dont have any
1070 - i have it on 87% tdp 1card and 85% tdp on 2nd ... 1st is on +185core (-502mems) and showing 1923+- MHz ... 2nd one is on +220core (-502 mems) and 1923+-MHz (sometimes jump up to 1949) ... BUT i cant actualy say, how much each cards is eating
EDITED: but it realy depends on algo you are using ... ethash or equihash are much easier to compute, so you can lower tdp as hell and increase core and mems to the heavens but when you are using algo that is heavy core only (skein, neoscrypt, decred, lyra .....) you must be carful with OC and TDP
