Quote:
Originally Posted by MikkiJayne
Just found out that the electricity at my workshop is now 14p a unit compared to 8p in 2015 when I last had a bill  That means my 980 has earned £21 and used £19 of electricity doing it, and since I have 2 years of electricity to pay for now (cos the landlord forgot about it until I reminded him last week) I'll have to sell the card to raise some cash  (unless demand for Ethereum goes up considerably after the fork - seems unlikely?)
It also renders the S9 somewhat pointless since it'd take a year to break even, although I guess it'd have some resale value since it would become unprofitable for me a lot sooner than someone with free electricity! How the L3+ would work out remains to be seen, since I don't believe the sales calculator on Nicehash.
Bonfire somewhat rained on 
Just switched tariffs at home and got 12.8p  |
Only £2 earned, It does suck a bit.
My electricity costs are £0.1243 day rate and £0.0729 night rate. Running 100W 24/7 it costs a bit under £8 per month.
I did notice that nicehash calculator is a bit optimistic. It only takes in to account GPU power consumption not the whole system, electricity price is 0.1USD by default and GPU prices are from USA and quite cheap. So they might choose $250 for a card, electricity price $0.1 and power consumption 160W. Reality is card price is £300, electricity £0.14 and power consumption with 1 card for older motherboard with lower efficiency PSU can be up to 400W
1 card is not going to do much and if you put 4 or 6 cards on one motherboard you are spreading the cost and power consumption of MB, CPU, RAM, HDD/SSD.
For example my old MB/CPU with 1 card would consume 100W in idle, new only 50 W with the same card and PSU. So on the old system running one card extra electricity costs on top of what card consumes would be £8 per month per card. If I run 4 cards on the new MB it's just £1 per card per month.
Regarding PSU's it's worth to remember that they are most efficient around 50% load and the quoted efficiency is usually based on this and efficiency can vary a lot between PSU's as well. If you use near 0% or 100% efficiency will be worse. For example I was running 2x1080Tis on 650W 80% PSU and it was consuming 700W from wall. Switching to 850W 91% PSU reduced it to 500W. That's 200W or £16 per month saving at a cost of £100 so will pay back in 6-7 months and there is some value in the old PSU which I can sell or reuse on lower lower load. Over 4 years I am £300 better off.
ROI time is important but I am looking at overall costs for expected lifetime. 4x RX480/580 cards will cost about £1200 an the rest of system £300-400. I expect to use cards for 4 years and to be able to sell them for £200 at the end. I think the rest of system should be usable after that with new cards. So the hardware cost is about £30 per month and electricity cost is about £50 for 600W and it is earning is varying £140-180 at current rates. In the winter it will also provide part of the heating for the house so little bit of saving there as well.
2x 1080Ti cost me £1300 +£100 for PSU, I already had the rest. I expect them to be £200 after 4 years, so about £25 per month hardware costs, £40 electricity at 500W and they are earning £90-£120 at current rates. I could cut costs about £4 per month switching to new MB/CPU/RAM but it will cost about the same to buy as what I will save over 4 years so no point really. I am planning to move them over to my HP Microserver anyway just need to build a frame the frame to hold them and sort out the wiring.