A bit off topic but I picked up a GTX 970 (Gigabyte Windforce 3x) only to realise the TDP of this card is not 145W but 250W. With stock BIOS, 100% power target and +160 Mhz core OC it draws 234 watts from the wall mining groestl (which seems to be the hungriest non-scrypt algo) on a 80+ gold PSU. It seems its efficiency plateaus around 40-60% power target limit depending on algo:
That is a 68-75% decrease in efficiency depending on algo compared to stock settings which is huge! This is important when profits are barely above electricity, for example if you pay $0.14 per kwh for electricity, going with yaamp x11 payout figures (which are not very profitable) one of these cards would earn 0.00371 BTC on stock settings while it would earn 0.01652 BTC after electricity at 40% limited power target in a month. On the other hand with more profitable coins/algos like quark, it's worth it to go full speed and overclock because it would end up earning more (0.08967 BTC on stock vs. 0.13118 BTC overclocked in a month). I thought it was quite interesting.
That is a 68-75% decrease in efficiency depending on algo compared to stock settings which is huge! This is important when profits are barely above electricity, for example if you pay $0.14 per kwh for electricity, going with yaamp x11 payout figures (which are not very profitable) one of these cards would earn 0.00371 BTC on stock settings while it would earn 0.01652 BTC after electricity at 40% limited power target in a month. On the other hand with more profitable coins/algos like quark, it's worth it to go full speed and overclock because it would end up earning more (0.08967 BTC on stock vs. 0.13118 BTC overclocked in a month). I thought it was quite interesting.