Thanks for the offer Richard :) The ducted cold air from the loft is working perfectly +++

Whattomine.com is now showing Ethash as being more profitable than Cryptonight for the rx580s. Unfortunately mine take another 40W each mining Eth but I'm at 100.1% capacity of my UPS already so no Eth for me http://www.corradov8.com/pics/banghead.gif

Cheap RX580 cards, too good to be true but I bought some as you do have ebay/PayPal protection if something goes wrong. Would not buy using business account though as I don't think you get any protection as business buyer.

https://www.ebay.co.uk/itm/PowerColo...53.m2749.l2649

Some RX570 also at low price https://www.ebay.co.uk/itm/SAPPHIRE-....c100009.m1982

Thanks for that +++ With some tweaking I've managed to get the RX580s to the same speed as Cast - 830H/s each, but using less power (just under 100W each) which is an unexpected bonus, plus the UPS is a little happier.

I still can't get the Vegas to what Cast can do though. They stubbornly remain 150H/s slower with Stak, or just crash if I turn the intensity up too much.

I've run stak on the 580s for about 12 hours now. Reported hash rate on Nicehash is not noticeably different, but the error rate certainly is:

http://forum.a8parts.co.uk/attachmen...1&d=1517134815

Left is Cast, right is Stak.

There's a thread on Github about this. Psychocrypt claims its a Nicehash problem which is BS. Stak has only recently started working at all with Nicehash in recent versions, and clearly its not right yet. It works fine on other Cryptonight pools, just not Nicehash, so I'll go back to Cast for running on Nicehash and keep Stak in reserve if I need to switch to another pool. I'd rather pay Cast's 1.5% fee than Stak's 7.5% rejected shares.

For reference, best performance from my RX580s is two threads each with intensity 1152 & worksize 8. That gives 414H/s per thread, 1660 total which is identical to what Cast does out of the box although admittedly at 10W less per card.

Antminer A3 is being made available again today at 6am, 8am, 1pm and 2pm GMT at a lot lower price of USD 980. 1 unit per user limit.

£99 card atm. from a 2 rating user. Probably a hacked account. Too good to be true there definitely!

Bitmain has S9 in stock right now

Do you mean T9 - the slower, supposedly more reliable version or is the S9 sold out again?