Crypto currency mining

MikkiJayne · #1 6th July 2017, 04:25 PM

Does it matter if all the graphics cards in the system are by the same vendor or not? I would expect them to all use the same driver so would also expect it wouldn't matter if they were a mix of different cards...

moltuae · #2 6th July 2017, 06:17 PM

No it shouldn't matter. We have some rigs with a few RX 480 cards from different vendors and they run happily with the same driver. We also have some rigs with a mix of different makes (ie AMD/nVidia) and models.

ainarssems · #3 7th July 2017, 01:31 PM

Have been experimenting with couple of RX480 cards including over/underclocking, flashing modded BIOS. On the 2 cards I have there is not much room for memory overclocking but a little GPU under-clocking does bring energy savings without affecting performance much. Modifying BIOS did see increase in MH/s from 24-25MH/s to 28MH/s but was unstable resulting in lot of incorrect shares so actual return was lower. I only modified memory timing, maybe if I added a little bit of extra voltage it might be more stable but I don't want to fry it. Some people are lucky enough with their cards to have BIOS mod and also run memory overclocked resulting in 30 MH/s but did not work out for me. I have another 2 different RX 480 turning up hopefully tomorrow so I will see how they do. Also RX580 shows as generating less on NiceHash profitability calculator but apparently are more acceptable to BIOS mods and can do over 30MH/s with mods. Somebody told me get rid of RX480 while they are still £300+ and get RX 580 and mod them. Seems like a reasonable advice since you can get RX580 for less than 480 it's just that RX580 are pre-order only with expected stock 31/07. Might also look at GTX 1080 Ti.

Another thing I would like to mention is that my first RX480 was huge but the second one reference design is the same size as my old GTX760 and would easily fit in case without cutting out HDD cage.

I am still having itch for Antminer L3+. If I were to buy it what would be the best way since I do not hold any crypto-currency or USD accounts but I do have empty Bitcoin wallet.

Mark, are you running all PC's on Windows or Linux as the licencing costs can mount up for several machines.

Another question is where does it stand with taxman? I suppose you can offset all your purchase and electricity costs against income and it would only count as income only when you convert your earned bitcoins to fiat currency.
My old PC with 2x RX480 is running 49MH/s with tweaked settings is expecting about £115 month at the current rate but this can vary a lot with £31 electricity costs so £600 investment should pay back in about 7 month, a bit longer than I was hoping for but should be still going for another 3 years or so after it has paid off. Obviously lot of unpredictable variables involved

MikkiJayne · #4 7th July 2017, 02:19 PM

Quote:

Originally Posted by ainarssems

Another question is where does it stand with taxman? I suppose you can offset all your purchase and electricity costs against income and it would only count as income only when you convert your earned bitcoins to fiat currency.

I was looking in to this the other day. In the UK its considered currency trading and subject to capital gains tax. Apparently there is a personal allowance of £11,100 on this, although I'm not sure if that's your income tax allowance or a separate one for cg. The amount of cg is dependent on how much income tax you pay - starts at 18% for basic rate income tax, then 28% for upper rate. There is a 3rd band too iirc.

Assuming its separate to your income tax allowance then 2 people can theoretically mine £22,200 a year without paying tax on it. Which is nice.

I got a payout of a whole £2.12 this afternoon! I only used £2.40 of electricity to get it too

I'm going to buy a GTX 980ti on Monday and see what that does. The 960 is quite vexing as it starts off mining at 84p a day when the Nicehash site says 86p, which is fine. If I leave it overnight its down to 12p a day which renders the whole business completely futile. It averages out to about 70% of what Nicehash says it should be doing. I'm hoping a 980ti will be more consistent, although I have no justification for that whatsoever...

Oh also, my 6-slot base model Proliant G7 uses the same power at idle (75W) and mining (195W) as my 2-slot mini-ATX desktop board. I can get a low-power Xeon for the G7 which might save a few watts, and also 750W power supplies for £20 each so I think thats going to be the hardware of choice, especially if I can optimise it a little more.

ainarssems · #5 8th July 2017, 11:26 AM

Out of the 2 cards I received today 1 seemed to respond well to BIOS mod but started to get errors later so have to switch back to stock BIOS.

I am either unlucky with 4 cards failing to respond well to BIOS mods or it's just not happening for RX480. Might try RX580 when they are in stock.

moltuae · #6 8th July 2017, 12:41 PM

Perhaps the BIOS mod works with some makes of RX 480 cards better than others.

Also, which driver version are you using? We found the November 2016 driver to be the most reliable. The driver released after that one has a lot of known issues. I haven't checked recently if there's a later/better driver.

ainarssems · #7 8th July 2017, 04:58 PM

I am using the latest recommended driver from AMD. What the BIOS mods are trying to do is to to get tighter VRAM timings so there is less time spent preparing VRAM to be read or written. I did experiment a bit with voltages as well today but it did not yield any improvements. It turns out the voltage you can change is actually memory controller voltage and not the actual VRAM voltage. VRAM voltage is fixed at 1.5V, memory controller will be somewhere 0.95-1.0V as shipped and supposedly can be safely increased to 1.15V. All my cards are 1.000V stock voltage and I tried 1.125V but it did not help. I think it's more down to the actual VRAM used on card which can be from different manufacturers ( Samsung, Hynix etc) and different batches. All of them will meat minimum specifications but some can be pushed further. All my cards have Samsung VRAM so maybe other manufacturers VRAM would be better off.

moltuae · #8 7th July 2017, 03:10 PM

Quote:

Originally Posted by ainarssems

Have been experimenting with couple of RX480 cards including over/underclocking, flashing modded BIOS. On the 2 cards I have there is not much room for memory overclocking but a little GPU under-clocking does bring energy savings without affecting performance much. Modifying BIOS did see increase in MH/s from 24-25MH/s to 28MH/s but was unstable resulting in lot of incorrect shares so actual return was lower. I only modified memory timing, maybe if I added a little bit of extra voltage it might be more stable but I don't want to fry it. Some people are lucky enough with their cards to have BIOS mod and also run memory overclocked resulting in 30 MH/s but did not work out for me. I have another 2 different RX 480 turning up hopefully tomorrow so I will see how they do. Also RX580 shows as generating less on NiceHash profitability calculator but apparently are more acceptable to BIOS mods and can do over 30MH/s with mods. Somebody told me get rid of RX480 while they are still £300+ and get RX 580 and mod them. Seems like a reasonable advice since you can get RX580 for less than 480 it's just that RX580 are pre-order only with expected stock 31/07. Might also look at GTX 1080 Ti.

I have wondered about GPU firmware/BIOS mods and whether they would be worthwhile but haven't yet gone down that route, so thanks for sharing your results

Quote:

Originally Posted by ainarssems

I am still having itch for Antminer L3+. If I were to buy it what would be the best way since I do not hold any crypto-currency or USD accounts but I do have empty Bitcoin wallet.

You could simply purchase some Bitcoin. I've previously use Bittylicious to buy BTC ( https://bittylicious.com ). Your daily limit may be less than you need until you're verified though. The process is pretty straightforward as long as you have a bank account that you can send instant transfers from. You simply enter your Bitcoin address, how much you want to buy and you're given the bank account details of the seller, along with a reference code. Make sure you enter the reference code correctly and don't include any other references/notes in the payment, especially not anything referring to Bitcoin (as you can probably imagine, banks don't like Bitcoin much and some have been known to block payments that refer to it).

Make sure you're aware of the risks before buying an L3+ though. We're taking a big gamble buying 3 of them but I'm hoping it will pay off. My gut feeling is that Litecoin will increase in value greatly now, especially as Bitcoin enters a potentially very shaky few months (due to uncertainty and the imminent SegWit developments). It's also the third largest and most popular cryptocurrency (not counting Ripple, which isn't a true, decentralised cryptocurrency). There's also a risk of course that the price could plummet. Nobody really knows. Be aware also of the risks of buying from China. I've not had any issues with Bitmain myself, but a unit could get damaged/lost in transit. You will also need to purchase a power supply with the Antminer and you will be asked to pay duty on both of them (at the usual rate) when they arrive. I don't mean to put you off -- If it wasn't a gamble we felt was worth taking we wouldn't have ordered 3 of them! -- but you do need to be realistic and be prepared for the worst outcome.

Quote:

Originally Posted by ainarssems

Mark, are you running all PC's on Windows or Linux as the licencing costs can mount up for several machines.

It really depends on personal preference and how legit you want to be. I mean Linux is great, if you're a Linux guru, but it can be a pain to get things working right if you're not. I don't work with Linux enough to be comfortable supporting it, so I'm using Windows. I know it all adds up, but a genuine Windows 10 OEM licence is relatively cheap compared to the rest of the mining rig so, for my customer's rigs at least, which are operating within a business premises/environment, we're sticking with fully licensed Windows 10 rigs --- It's more than my reputation is worth not to. You can actually buy Windows 10 OEM licences from ebay for about £30 though. Probably not genuine but, in a home environment, as long as the licence key works, do you care? Alternatively, you can go down the perpetual evaluation route: Windows 10 will work indefinitely without a key; there's just a few limitations, such as disabled desktop customisation. After all, these are just test rigs, right?

Quote:

Originally Posted by ainarssems

Another question is where does it stand with taxman? I suppose you can offset all your purchase and electricity costs against income and it would only count as income only when you convert your earned bitcoins to fiat currency.

Essentially yeah, though it probably depends on your own situation. I'm self employed and I work in IT (mainly from my home office) so any IT purchases and electricity expenses lower my profits and reduce my tax bill.

More info here:

http://sterlingcoin.org/uk-tax-rulings/

http://www.hmrc.gov.uk/briefs/vat/brief0914.htm

moltuae · #9 7th July 2017, 04:58 PM

Something else I should mention about the Antminers (if I haven't mentioned it already ) .... they're quite loud!

ainarssems · #10 7th July 2017, 07:26 PM

Quote:

I got a payout of a whole £2.12 this afternoon! I only used £2.40 of electricity to get it too

I did as well, was not even expecting it as it always said next payout 11/07. I got a bit more, exact value may vary depending on Bitcoin exchange rate but about £14. That was with alot of downtime messing around and trying different things.

Quote:

I'm going to buy a GTX 980ti on Monday and see what that does

I am still a newbie but from what I gathered so far GTX10xx is different architecture and can run more algorithms so should be more future proof. 980 Ti will probably be a bit more expensive than 1060 6GB but should generate a bit more income, for me if I think about using it 3-4 years I would go for 10xx series for more future proofing. To mine Ether you need at least 3GB VRAM now but that is expected to rise to 4GB soon, so 3GB 1060 is out of question and 4GB cards probably will not last 3-4 years. So it needs to be over 4GB for me be it nVidia 6GB or AMD 8GB. I am thinking about buying couple of nVidia cards myself for variety/ risk spreading but it will be 1080 or 1080 Ti. Still like I said I am still newbie so my views are not necessarily correct just putting it out there for consideration.